JPH06268045A - Manufacture of integrated circuit - Google Patents

Abstract

PURPOSE: To obtain an integrated circuit which is not polluted by contaminats, by putting a wafer in a vacuum-tight retainer after the wafer is carried after treatment process, and carrying the wafer in the state of vacuum. CONSTITUTION: A wafer retainer 10 which is carried after treatment process is arranged in a vacuum load lock 12. After a lid 20 of the load lock is closed, high voltage purge is applied via a manifold 22, and then the pressure of a chamber is gradually decreased to 10<-4> Torr or lower. After the pressure of the load lock 12 is decreased and the state is maintained for several seconds, a door is opened and a shaft 24 is rotated. The door 14 is opened until a sensor detects that the door 14 is completely opened. After that, the operation of a transfer arm is started. That is, the transfer arm 28 can reach the inside of the retainer 10 or reach an adjacent treatment chamber via a port 30.

Description

Description: TECHNICAL FIELD [Detailed description of the invention]

[0001]

INDUSTRIAL APPLICABILITY The present invention relates to a method for manufacturing an integrated circuit.

0002.

[Conventional Techniques and Problems] One of the basic problems in manufacturing integrated circuits is particulate matter. Integrated circuit processing 2
Due to two trends, this problem is getting harder and harder.
First, as the dimensions of the device become smaller and smaller, it becomes necessary to avoid the presence of smaller particles. This makes it increasingly difficult to ensure that a clean room is actually clean. For example, a clean room of class 1 (having one particle per cubic foot) for particles over 1 micron is 1
Class 1,000 if you count particles up to 00 Å
Or even worse.

Secondly, there is an increasing desire to use integrated circuit patterns with large dimensions. For example, the dimensions of integrated circuits larger than 50,000 square mills are much more in use today than they were five years ago.

For this reason, particulate matter is not only an extremely important source of loss in the manufacture of integrated circuits, but its importance will continue to grow very rapidly. Therefore, it is an object of the present invention to provide a generally applicable method of manufacturing integrated circuits that reduces the impact of particulate matter contamination on the process.

One of the main sources of particulate matter contamination is that produced by humans, including particles emitted from the human body and particles created by operators of equipment moving around inside semiconductor processing equipment (front ends). Is. To reduce this, the general trend in the industry over the last few years has been to use more automated transport operations. At this time, the engineer
For example, a cassette of wafers is loaded into the machine, then the machine automatically passes the wafers one by one from the cassette (to perform the necessary processing steps) through the machine and then back into the machine.
Make sure that the technician does not have to touch the wafer.

However, efforts in this direction have made it clear that the second important source of particulate matter is important. This is a particulate matter generated internally by the wafer and / or transfer mechanism. That is, when the surface of the wafer moves slightly in contact with another hard surface, some particulate matter (of silicon, silicon dioxide or other material) tends to be released. The density of particulate matter inside an ordinary wafer support is typically very high due to these sources of particulate matter. Moreover, many conventional wafer transport mechanisms themselves generate significant amounts of particulate matter.

The present invention advantageously solves this problem by providing a wafer support that reduces the generation of particulate matter in transit in several ways. First, the vacuum support door has an elastic element that lightly presses the wafer against the back side of the support box. Therefore, when the box door is closed, the wafer is restrained so that it does not rattle.
This reduces the internal generation of particulate matter. Second, each side of the wafer is supported by a lightly sloped shelf, so there is very little contact between the surface of the wafer and the surface of the shelf (line contact). This reduces the generation of particulate matter due to wear on the wafer surface.

The present invention not only reduces the generation of particulate matter in the support during transport and storage, but also transports the wafer face down under high vacuum to allow the wafer to be transported and stored. It also advantageously reduces the transport of particulate matter to the surface. So far, no one has addressed this issue.

This wafer support design can be used in conjunction with the wafer transport mechanism of the present invention, which is described in a separate application, to result in a complete wafer transport device with low particulate matter.

The current wafer charging mechanism used in the semiconductor industry is mainly composed of three basic types. That is, a belt-driven wafer transport device, an air truck-driven wafer transport device, and an arm-driven wafer transport device (either vacuum coupling or nest-shaped retention is used to hold the bottom or edge of the wafer). .. However, all types of equipment move the wafer face-to-face when moving in and out of the support, and move the wafer support vertically during loading and unloading operations, ranging from atmospheric pressure to low vacuum. It is typically accompanied by the need to transfer the wafers under the pressure of and unload the wafers in the reverse loading order. Therefore, the conventional method has a number of important drawbacks as described below.

First, the wafer transported face up tends to capture the particles generated by the particle generation mechanism inside the wafer support or inside the wafer loader device.

Secondly, the vertical movement of the wafer support during the loading and unloading operations causes the wafer to rattle in the support, resulting in a large number of particles. There is a risk that these particles will fall directly onto the effective surface of the adjacent wafer that rests face up in the support.

Third, the belt mechanism typically rubs the bottom of the wafer during loading and unloading operations, also creating a large number of particulate matter by wear.

Fourth, the air truck transport device creates a large number of particulate matter around it due to the flow of air, many of which rest on the effective surface of the wafer.

Fifth, the drive mechanism of many loader modules is housed in the same area as the open wafer support and is very close to the wafer to be processed. This is likely to result in a significant amount of contamination.

Sixth, when loading and unloading the wafer, the mass of the combination of the support and the wafer changes, which may affect the reliability and positioning of the vertical drive portion of the wafer support. Large wafer (eg 1)
This is especially true when dealing with (50 mm or more).

Seventh, it is typical to use two loading modules for each processing unit, thus gradually loading into one cassette and loading wafers from this processed cassette into a second cassette. Load to.

Eighth, since the machine must be idle while removing the cassette, the efficiency of use of the device is reduced each time a new cassette of wafers is loaded into or from each processing unit.

The present invention provides an advantageous solution to all of the problems mentioned above and provides significantly improved wafer handling and loading operations with less particulate matter.

One important advantage of the present invention is the ability to transport, load and unload wafers without encountering atmospheric or low vacuum conditions. About 10
^{This is extremely useful because at a pressure of -5} torr, there is not enough Brownian motion to support particulate matter larger than about 10 nm, and such particulate matter falls out of this low pressure atmosphere relatively quickly. ..

In FIG. 7, particles having different dimensions are one-size-fits-all at atmospheric pressure.
Shows the time required for the torr to fall. 10^-FiveTorr (1E
At a pressure of -5 torr) or less, with 10 nm particles
Even, it falls 1 meter per second, and particles larger than this fall
Note that it will fall even faster. (Large particles
It simply falls ballistically due to gravitational acceleration. ) For this reason, 10
^-FiveAtmospheres with pressures below torr are at 10 nm or above
Large particles are transported only ballistically, resulting in irregular airflow
Or due to Brownian motion drift, the importance of the wafer
It means that there is no possibility of being carried to another side.

The relevance of this curve to the present invention is that the invention does not expose ^{the wafer to pressures higher than 10-5 torr.}
It is the first to provide a method of transporting a wafer from one processing unit to another, including loading and unloading steps. That is, from the time the wafer is first loaded into the vacuum processing unit, which may be a scraping and pumping down station, until the processing is complete, the processing process itself (eg, a normal photoengraving station or) Wafers are never exposed to particulate matter carried into the air unless higher pressures are required (such as in wet processing steps). this is,
This means that the overall likelihood of particulate matter collecting on the wafer is greatly reduced.

An important key to this advantage is that the present invention provides methods and devices for loading and unloading vacuum supports under high vacuum.

The present invention provides a load lock. This load lock opens the vacuum wafer support under vacuum, removes the wafers from the support in any random access order, in the desired order, and takes the wafers one by one, like a plasma etch chamber. Includes a device that passes through a port to an adjacent processing chamber. Further, the load lock of the present invention can close and reseal the wafer support.
Therefore, even if the load lock itself is set to atmospheric pressure and the wafer support is taken out, the vacuum inside the wafer support is not broken.

A special advantage of the preferred embodiments of the present invention is that the mechanical equipment preferred to be used for wafer transfer is very small. That is, the transfer arm is pivotally attached to the arm support, and a gear device or a chain drive device is provided inside the arm support so that the rotation of the arm support causes twice the rotation of the transfer arm with respect to the arm support. By setting, it is possible to stand still in a fixed position, and a gap larger than the length of the arm support is not required in one direction, but a simple rotation axis can be used in either of the two directions. The movement provides a cozy device that can be extended to the length of the arm support plus the length of the transfer arm.

Another advantage of the preferred embodiments of the present invention is
The motors used to extend and change the height of the transfer arm are all held inside the exhaust manifold, which exposes the particles generated by these moving mechanical elements to the wafer. There is no tendency to reach the inside of the load lock chamber.

Another advantage of the present invention is to provide a transfer arm that allows the wafer to be handled face down so that contact with the transfer arm causes minimal damage to the area of the device. ..

Another advantage of the present invention is that the invention produces very little particulate matter during the handling operation.
The purpose of the present invention is to provide a wafer transfer device capable of handling wafers.

Another advantage of the present invention is that the present invention provides a transfer device capable of handling a wafer without substantially generating particulate matter due to wear because there is substantially no sliding contact. It is to be.

Another advantage of the wafer transport mechanism of the present invention is the simplification of the control device. That is, the transfer arm preferred to use has only two degrees of freedom and the position is aligned so that the control of the transfer arm does not require a sensor to detect the position of the arm or the force applied to the arm. , (By using a step motor or equivalent device), it can be done very easily.

A related advantage of the wafer transport mechanism of the present invention is that it is a stable mechanical device. That is, the small error in positioning does not accumulate, and due to the inherent negative feedback performed by using a certain mechanical element,
It is to decay and disappear. This facilitates the advantage of being easy to control.

Another advantage of the present invention is that the wafer handling equipment used in the load lock occupies a minimum volume. Due to the small volume of the load lock, the vacuum cycle can be performed at high speed without the need for a very expensive large vacuum pump.

A more important result of the volumetric efficiency of the wafer transport device of the present invention is that the upper portion of the load lock (which exposes the defect-prone surface of the wafer being transported) has a small surface area. .. It is desirable that the surface area of the surface of the wafer within the line-of-sight range is as small as possible, and it is also desirable that the surface area very close to the surface of the wafer, whether within the line-of-sight range or not, be as small as possible. The entire surface area of the upper part of the load lock (ie, the part above the exhaust manifold) carries two risks. First, all surface areas absorb gas, so the larger the surface area in the upper chamber, the more
It becomes more difficult to evacuate to a high vacuum. Second, and more importantly, all surface areas can retain adhesive particulate matter, which later mechanical vibrations or shocks, even under high vacuum. May be ballistically extruded onto the surface of the wafer. Therefore, the volumetric efficiency of the load lock of the present invention means that the possibility of ballistic transport of particulate matter to the surface of the wafer is reduced.

Further, another embodiment described in this continuation application states that the wafer itself is in a load lock and does not see any surface exposed to particulate matter when loading the support onto the lock. It has another advantage. In this embodiment, the wafer support has a vertically removable cover that can be sealed in vacuum instead of a hinged door that can be sealed in vacuum, and the support is in the upper chamber (main load lock). ), The support body is lowered from under the cover in the lower chamber, during which the cover remains in place and covers the opening between the upper and lower chambers. For this reason, the wafer support main body and the wafer inside the wafer support not only never see the dirty surrounding atmosphere, but also never see the surface exposed to the dirty surrounding atmosphere.

Another advantage of the small wafer handling equipment in the load locks of the present invention is that such equipment consumes excessively clean room floor space, which is invaluable. Do not do it.

Another advantage of the wafer support described in this application is that the wafer support cannot be accidentally opened outside the clean room. A substantial yield problem in conventional clean room processing is that the wafer is accidentally or inadvertently exposed to particulate matter by opening the wafer support outside the clean room environment. Is. However, with the wafer support of the present invention, this is because the differential pressure of the support against the door keeps the support tightly closed except when the support is in vacuum. It is essentially impossible. This is another reason why the invention is advantageous in allowing wafers to be easily transported and stored outside the clean room environment.

In another group of embodiments of the invention, the process module, which may optionally have one process station or two or more process stations, is one of the inventions. More than one load lock is installed. Therefore, it is possible to load the wafer again on the other load lock while continuing the processing on the wafer carried in by one load lock. In addition, the provision of two transfer mechanisms means that if one of the transfer devices in the load lock has a mechanical problem, while reading the technician to fix the mechanical failure, the other load lock By using transfer, it means that the production of the processing unit can be continued. Such a group of examples has the advantage that the volume is even higher.

The present invention provides a method of manufacturing an integrated circuit. In this method, a plurality of wafers are provided in a wafer support box that can be vacuum-sealed, the wafer support box has a cover that can be vacuum-sealed in the main body, and the cover is supported in the main body. It is detachable from the main body in a substantially normal direction with respect to the plane surface of the wafer, and has a partial floor having an opening in the wafer and a stage arranged in close proximity to the floor and arranged below the opening. The wafer support is placed in a vacuum-sealed load lock upper chamber, the load lock upper chamber is ^{depressurized to a pressure of less than 10-4} tolls, the stage is lowered and the cover is in the upper chamber. The wafer remains under vacuum until the body containing the wafer is lowered into the lower chamber and the desired series of processing operations is completed, while remaining supported on a partial floor. In the desired order, the wafer supports are transferred to one or more selected process stations encapsulated in an adjacent vacuum-dense space connected to the lower chamber, after which the stage is raised to raise the wafer support. It comprises the steps of recombining the body with the cover of the wafer support and achieving vacuum sealing between them, ventilating the upper chamber to the surroundings and removing the wafer support from the upper chamber.

The present invention has a wafer support body that includes a support including a crosspiece tapered to support a flat disc in substantially line contact rather than surface contact, the support. It is continuous with the base, the base includes a vacuum seal surrounding the side support, and further has a cover in the form of being combined with the vacuum seal of the wafer support body, the cover, the vacuum seal and the said. The body limits the vacuum-tight jacket, and the cover provides a wafer support that is detachable from the body in a substantially normal direction with respect to the vacuum-sealed plane.

In the present invention, there is a main body including a side wall and a cover that can be sealed together with the main body so as to form a vacuum tight seal, and the side wall limits a groove for holding a wafer of a predetermined size. Provided is a wafer support having a plurality of crosspieces and having at least one surface of the side wall crosspiece sloped so as to be offset by at least 5 ° from a direction parallel to the plane of the groove.

The present invention has a main body including a side wall and a cover that can be sealed together with the main body so as to form a vacuum tight seal, and the side walls both limit the groove holes for holding a wafer of a predetermined size. It has a plurality of crosspieces, and at least one surface of the crosspiece of the side wall is sloped so as to deviate at least 5 ° from the direction parallel to the plane of the groove, and the inner surface thereof is elastic. Provided is a wafer support having an element and fixing the elastic element so as not to freely move a wafer of the predetermined size.

In the present invention, as a method of transporting an integrated circuit wafer during manufacturing, the wafer is placed in a vacuum-tight support having a main body including a side wall and a cover that can be sealed together with the main body so as to form a vacuum-tight seal. The side wall has a plurality of crosspieces that limit the groove holes for holding the wafer having the desired dimensions, and at least one surface of the crosspiece of the side wall has the groove hole. Provided is a method in which a gradient is provided so as to deviate by at least 5 ° from a direction parallel to the plane.

In the present invention, as a method of transporting an integrated circuit wafer during manufacturing, a vacuum is provided in a vacuum-tightened support having a main body including a side wall and a cover that can be sealed together with the main body so as to form a vacuum-tight seal. The wafer is carried in a state, and each of the side walls has a plurality of crosspieces that limit the groove holes for holding the wafer having the planned dimensions, and at least one surface of the crosspieces of the side wall is a flat surface of the groove holes. It is sloped at least 5 ° from its parallel direction, and the support has an elastic element on its inner surface that holds the wafer of the intended size firmly so that it does not move freely. Provide a method.

The present invention includes a step of transporting an integrated circuit wafer during manufacturing, the transport step being vacuum tight with a body including the side walls and a cover that can be sealed with the body to create a vacuum tight seal. Including the step of transporting the wafer in a vacuum state in the support of the side wall, each side wall has a plurality of crosspieces limiting a groove for holding a wafer of a predetermined size, on at least one surface of the crosspiece of the side wall. Is a wafer that is sloped by at least 5 ° from a direction parallel to the plane of the groove, the support has an elastic element on its inner surface, and the elastic element has the expected dimensions. The wafer is inside the wafer support while the wafer support is kept closed by the differential pressure by increasing the integrated circuit cross-force to hold it firmly so that it does not move freely. Provided is a method of manufacturing an integrated circuit including a step of keeping it in a vacuum state.

In the present invention, a desired processing step is performed at a plurality of process stations separated by an atmosphere of substantially atmospheric pressure, and an integrated circuit wafer manufactured halfway is transported between the process stations. do it,
Each wafer includes a step of performing processing steps in a scheduled order, and the transporting step is performed after the processing steps, and after the wafers have been transported, the wafers are placed in a vacuum-tight support. Provided is a method for manufacturing an integrated circuit including a step of transporting the wafer in a vacuum state.

Next, the present invention will be described with reference to the drawings.

[0047]

[Example] Next, the configuration and usage of the currently preferred embodiment will be described in detail. However, the idea of this invention
It is an idea that can be applied over a wide range of cases that can be implemented in a wide variety of cases, and the specific examples described herein merely illustrate specific methods of utilizing the present invention.
Please note that this does not limit the scope of the invention.

FIG. 1 shows an embodiment as a sample of the present invention. This example shows the wafer support 10 in the vacuum load lock chamber 12. Wafer support 10
More details are also shown in FIG.

The support 10 shows a state in which the door 14 is open. It is preferable to have a vacuum seal 13 where the door 14 meets the body of the support 10, so that the wafer support can be carried at a pressure below atmospheric pressure for at least several days (preferably at least several tens of days) inside. No leaks that would increase the pressure ^{above 10-5 torr.}

The wafer support 10 is a platform 18.
(This is only partially shown in FIG. 1, but is shown in more detail in FIG. 9), when the technician puts the wafer support 10 inside the load lock 12. The position of the support 10 can be accurately known. In a currently preferred embodiment, the wafer support 10 has protrusions 16 that engage the vertical slots 17 secured to the alignment platform 18, so that the technician can use the support to support the platform 18. The support can be slid along this groove until it is seated, thus ensuring that the position of the support 10 is clearly visible. In the currently preferred embodiment, the platform 18 is the wafer support 10.
2 arranged to engage the tapered hole 23 on the lower side
It has one taper pin 21 (one conical, one wedge), but as will be apparent to those skilled in the art, a wide range of other devices to ensure mechanical alignment. Can be used.

The support 10 preferably has a safety catch 15, which holds the door 14 so that it does not open.
However, under normal transport conditions, this safety catch is not necessary as atmospheric pressure keeps the door 14 closed to the internal vacuum of the support. When the support 10 is placed inside the load lock 12, the fixed finger 19 hits the safety switch 15 and releases it, so that the door 14 can be opened.

When the support 10 is combined with the platform 18, the door 14 also engages with the door opening shaft 24. Door 1
4 has a shallow groove on its underside, which preferably meets the finger and arm 25 at the top of the door opening shaft 24. Therefore, reduce the pressure of the load lock,
The door can be opened by the door opening shaft 24 after the differential pressure no longer holds the door 14 in the closed state.

After the technician places the wafer support 10 in the vacuum load lock 12 and closes the load lock lid 20, the manifold 2 inside the load lock lid 20
It is preferable to apply a high pressure purge (dry nitrogen or other clean gas) via 2. This high pressure purge creates a vertical flow, tends to transport particles downwards, and helps to blow off some of the large particles that have accumulated on the wafer support 10 while exposed to atmospheric conditions. Become. After this initial purging step (eg for about 30 seconds or longer), the chamber is slowly reduced in pressure to ^{10-4 torr or less.} This depressurization step is preferably performed relatively slowly so as not to wind up irregular particulate matter. That is, low pressure causes particles to fall out of the air, but these particles are still above the bottom of the chamber and should not be rolled up if avoided.

The interior of the vacuum load lock should be kept at ^{10-4 to 10-5} torr for a few seconds to ensure that the particulate matter carried by the air actually falls out of the air in the chamber.
It is preferable to ensure that all particles that can fall out of the air fall.

As an example modified by the voluntary choice of the present invention, a side wall and a bottom may be popped out by mechanical vibration using a sloped bottom and / or a polished side wall of the load lock. It may be advantageous to reduce the population of particulate matter that sticks to it. The present invention significantly alleviates the problem of air-carried particulate matter, which has always been the main form of particulate matter transport, and thus the problem of ballistically transported particulate matter. Can be effectively taken up. A related deformation by voluntary choice is to use a vacuum particle counter in place in the upper chamber, which can detect any increase in the population of particles within a significant volume. You can. Such on-site particle counters use resonant circuits to measure charge transfer within high-voltage vacuum gap capacitors.
Alternatively, it can be constructed by using a laser-driven optical cavity having a multiple bending optical path, or by other means.

A nitrogen shower prior to the initial decompression, optionally using a particulate matter sensor (or a second particulate matter sensor that is better suited to detect particulate matter at higher pressures). Can be controlled. That is,
Instead of simply taking a nitrogen shower for a period of time, the shower can be extended if the particulate matter monitor indicates that the box is in an unusually dirty environment. Reduce the load lock to soft vacuum (using a coarse pump) and
It may then be desirable to divert the gas through the nitrogen shower port to create a downward flow. If the particulate matter monitor shows that the particulate matter level is still excessive when the load lock reaches a given soft vacuum pressure, the load lock can be started by initiating another nitrogen shower cycle. The soft vacuum (eg 100
It may be desirable to use a cycle that raises the pressure from (about Milittle) to atmospheric pressure again.

Note that it is preferable to connect the vacuum gauge 62 inside the load lock chamber. It is preferred that the sensor 62 includes a high voltage gauge (such as a thermocouple), a low pressure gauge (such as an ionization gauge) and a differential pressure sensor that accurately senses when the internal pressure of the load lock is in equilibrium with the atmosphere. For this reason, the door of the support 10 cannot be opened until these instruments indicate that a good vacuum has been achieved inside the load lock.

After the coarse pump (not shown in the drawing) depressurizes the chamber to soft vacuum, the gate valve 39 is opened, the turbo molecular pump 38 is connected to the inside of the load lock, and then the turbo molecular pump 38 is operated. The pressure can be reduced to ^{10-5 torr or less.}

At this point, the pressure inside the wafer support 10 and the vacuum load lock 12 is more or less balanced, and the door 14 can be operated by operating the motor 26. The motor 26 is connected to the door opening shaft 24 via the vacuum passage portion 25.

When the door 14 is in the fully open position and the door 14
It is preferable to provide two sensor switches inside the vacuum load lock 12 to ensure when is completely closed. That is, after depressurizing the load lock 12 and keeping it in that state for several seconds, the door opening shaft 24 is rotated.
Door 1 until the sensor detects that the door is fully open
Open 4. During this time, the transfer arm 28 has a door 14
It is preferable to keep the door in place at a height below the bottom of the door so that there is a gap to open it. After the sensor detects that the door 14 is fully open, the transfer arm can be started to operate.

The transfer arm 28 preferably has two degrees of freedom. With one direction of motion, the transfer arm 28 can reach into the support 10 or through the port 30 to the adjacent processing chamber. The other degree of freedom corresponds to the vertical movement of the transfer arm 28, which allows one to choose which wafer in the support 10 to take out or in which groove the wafer should be placed.

In a currently preferred embodiment, the elevating drive motor 32 is used to control the height of the transfer arm 28, and the arm drive motor 34 controls the extension and retreat of the transfer arm 28. In the currently preferred embodiment, both motors do not require a vacuum passage and are housed in an exhaust manifold 36. The manifold extends from the load lock 12 to the vacuum pump 38, which pump may be, for example, a turbo molecular pump. Further, the exhaust manifold 36 does not open directly into the load lock chamber 12, but has an opening 40 at the top thereof. That is, it is preferable that the exhaust manifold 36 is configured so that there is no line-of-sight passage from the drive motor 32 or 34 or from the pump 38 to the load lock chamber. This helps reduce the ballistic transport of particulate matter from such moving elements into the load lock chamber.

The elevating drive motor 32 is a small platform 4.
It is preferable to connect the two so as to drive them up and down, and it is preferable that the arm drive motor 34 is attached to the platform 42.

In a currently preferred embodiment, a link mechanism is used inside the rotatable transfer arm support 44 to allow the transfer arm 28 to move very cozyly. It is preferable that the transfer arm support 44 is connected to a rotary rod, and the rotary rod is driven by the arm drive motor 34, but the arm support 44 is preferably attached to a non-rotating tubular support 46. It is preferable to use an internal chain and a sprocket-type link mechanism so that the seam between the arm support 44 and the transfer arm 28 moves at twice the angular velocity of the seam between the arm support 44 and the tubular support 46. (Of course, instead, many other mechanical link mechanisms can be used to do this.) That is, when the arm support 44 is in place, the wafer 48 supported is Approximately above the tubular support 46, but the arm support 44 is the tubular support 4
When rotated 90 ° with respect to 6, the transfer arm 28 rotates 180 ° with respect to the arm support 44 so that the transfer arm can enter straight into the wafer support 10 or through the port 30. It means that you can enter the next processing room straight. This link mechanism was 1984 1
It is described in detail in the pending US patent application serial number 664,448, which was filed on April 24.

The transfer arm 28 has a thickness of, for example, 0.030.
It is preferably a single piece of inch steel. The transfer arm has three pins 50 for supporting the wafer. It is preferred that each pin 50 has a small cone 52 over a small shoulder 54. The cone 52 and shoulder 54 are preferably made of a soft material that does not scratch the silicon. In the currently preferred embodiment, these parts (which are the only parts of the transfer arm 28 that actually come into contact with the wafer to be transported) are Adel (a thermoplastic phenyl manufactured by Union Carbide). -It is preferable to make it from a high temperature plastic such as acrylate) or delrin (that is, a plastic having a relatively small tendency to degas in a vacuum state). Positioning pin 5
Transfer arm 28 by using cone 52 in the center of 0
It is possible to correct a very slight misalignment of the wafer with respect to. In other words, the wafer transport device of the present invention is a stable mechanical device in which small misalignments during successive operations do not accumulate and are attenuated.

Note that when positioning the wafer 48 as shown, one of the three pins 50 touches the flat portion 56 of the circumference of the wafer. That is, in this embodiment, the three pins 50 of the transfer arm 28 do not limit the circle having the same diameter as the diameter of the wafer 48 to be handled.

Box 10 to ensure that the flat portion 56 of the wafer does not interfere with the accurate handling of the wafer.
Has a flat surface on its inner back side so that the flat portion 56 of the wafer 48 is in contact with it. A spring compression element inside the door 14 presses each wafer against this flat surface when the door 14 is closed so that the wafers do not rattle during movement. This is also when the door 14 is opened
It is a guarantee that the location of the flat portion 56 of each wafer 18 is accurately known.

Therefore, when the box 10 is in the chamber 12 and the door 14 is open, the elevating drive motor 32
Brings the transfer arm 28 to just below the height of the first wafer to be removed, then activates the arm drive motor 34 to bring the transfer arm 28 inside the box 10. Put in. By operating the elevating drive motor 32 for a short time, the transfer arm 28 is raised at this position, and the three pins 50 on its circumference place the desired wafer on the crosspiece 6 on which it rests in the support box 10.
Lift from 0.

The crosspiece 60 has a tapered surface rather than a flat surface, and the contact between the crosspiece 60 and the wafer 48 resting on it is line contact rather than surface contact and is restricted to the edges of the wafer. Note that it is preferable to do so. That is, while conventional wafer supports may have surface contact over a considerable area of many square millimeters, the "line contact" used in the present invention is typically much smaller, a few square millimeters or less. It only touches over an area. "Line contact" as used in this embodiment of the present invention
Another definition of is that the wafer support is 1 from its edge.
It is in contact with the surface of the wafer only at points less than a millimeter.

By raising the transfer arm 28 in this way, the desired wafer 48 is picked up and rests on the cone 52 or shoulder 54 on the three pins 50 of the transfer arm 28.

In an embodiment currently considered preferred, the crosspiece 60 has a center spacing of 0.187 inches within the box. This center spacing, minus the thickness of the wafer, must have sufficient clearance for the height of the transfer arm 28 plus the height of the pins 50, but must be much larger. There is no. For example, in the currently preferred embodiment, the thickness of the transfer arm is about 0.080 inches, including the height of the cone 52 on the transfer pin 50. The thickness of the wafer itself (in the currently preferred embodiment using a 4 inch wafer) is about 0.21 inch, which results in a gap of about 0.085 inch. Of course, a wafer with a larger diameter has a larger thickness,
Since the dimensions of the box 10 and the center spacing of the crosspieces 16 inside the box 10 can be appropriately changed, the present invention is particularly suitable for such a wafer having a larger diameter.

Thus, after the transfer arm 28 picks up the desired wafer 48, the arm drive motor 34 is actuated to bring the transfer arm 28 into place.

The elevating drive motor 32 is then actuated to bring the transfer arm 28 to a height at which it can reach the port 30.

Unlike the gate 31 shown in FIG. 8, the port 30 is preferably covered by an isolation gate 31. It is preferable that the gate 31 seals the port 30 without sliding contact. (As before, the absence of sliding contact is advantageous in reducing the amount of particulate matter generated inside.)

In this embodiment, the isolation gate 31 on the port 30 is preferably operated by an air cylinder, but a step motor may be used instead. Therefore, a total of four motors are used. That is, two that use the vacuum passage portion and two that are preferably housed in the exhaust manifold 36. The arm drive motor is then activated again to extend the transfer arm 28 through the port 31 to the adjacent processing chamber.

The adjacent processing chamber may be any of many different types of processing units. For example, this processing unit may be a driving device, a plasma etching unit, or a depositing unit.

In a currently preferred embodiment, the transfer arm through the port 30 mounts the wafer 48 on three pins 50 as shown in FIG. 8, similar to that used for the transfer arm itself. Let me. (Port 30 is the arm 28
Has a vertical height that allows it to move slightly vertically while extending through port 30, so that the arm 28 lifts the wafer from pin 50 in the processing chamber or on top of this pin. Note that it is preferable to allow vertical movement for lowering. )

Alternatively, the processing chamber may have a jig with a crosspiece with a gradient similar to that of the crosspiece 16 in the transfer box, or any other mechanical device that receives the wafer. You may have. However, in any case, the equipment used to receive the transferred wafer has a gap underneath the wafer (at least during the transfer) so that the transfer arm 28 can place or remove the wafer. It must be able to enter the underside of the wafer. Pin 5 to receive the transferred wafer
When 0 is used, it may be desirable to provide a bellows motion or a vacuum passage to allow the wafer support pins to move vertically in the processing chamber. That is, for example, the processing chamber is a plasma etching section or RIE (reactive ion etching).
In the case of a portion, a through portion can be provided to position the wafer on the acceptor after the transfer arm 28 has been retracted from the wafer passage.

Of course, the processing unit may be a technical inspection unit. A vacuum-isolated microscope objective can inspect a wafer in a vacuum state (using a properly bent optical path) in a face-down orientation. This means using technician inspections extensively, where appropriate, without taking the technician's time and without causing the quality degradation of the clean room, which can be caused by heavy traffic in the clean room. Can be done.

In any case, it is preferable to retract the transfer arm 28 and close the isolation gate above the port 30 while the process is in progress. After the process is complete, the isolation gate above the port 30 is reopened, the arm 28 is extended again, the elevating drive motor 32 is operated for a short time so that the arm 28 picks up the wafer 48, and the arm drive motor 34 is reopened. Actuate to bring the transfer arm 28 back into position. After that, the elevating drive motor 32 is operated to transfer the transfer arm 28.
Is brought to the correct height to align the wafer 48 with the desired groove inside the wafer support. The arm drive motor 34 is then actuated to place the transfer arm 28 into the wafer support 10 so that the freshly processed wafer 48 sits on a pair of crosspieces 60. After that, the elevating drive motor 32 is operated for a short time to lower the transfer arm 28 so that the wafer rests on its own crosspiece 60, and the arm drive motor 34 is operated to retract the transfer arm 28 to a fixed position. The series of steps just described is then repeated and the transfer arm 28 selects another wafer for processing.

Using the mechanical link mechanism of the transfer arm 28 and the arm support 44 as described above, if the lengths between the centers of the transfer arm 28 and the arm support 34 are equal, the transferred wafer will be Move exactly in a straight line. This is advantageous because the sides of the transferred wafer do not hit or scratch the sides of the box 10 when the wafer is pulled out of or pushed into the box. That is, even if the clearance of the wafer support box is relatively small (which helps reduce the generation of particulate matter due to the rattling of the wafer during transport in the support), the wafer is due to the metal side of the box. There is no risk of generating particulate matter due to wear.

In this way, processing is continued on a wafer-by-wafer basis until all the wafers (or at least as many wafers as desired) within the support 10 have been processed. At that point, the transfer arm 28 was left empty and returned to its home position, lowered below the lower edge of the door 14, and port 30.
Close the isolation gate above. The door opening shaft 24 is then rotated to close the door 14 and support when the first contact of the vacuum seal between the door 14 and the flat front surface of the support 10 occurs and thus the pressure in the load lock increases. The body is ready to be sealed (by differential pressure). At this time, load lock 1
2 can be pressurized again. When the differential pressure sensor of the pressure gauge 62 shows that the pressure has reached atmospheric pressure, the lid 20 of the load lock can be opened and the wafer support 10 (which is sealed by the differential pressure at this time) can be taken out by hand. You can. In a preferred embodiment, a bending handle 11 is provided on the upper side of the support to assist in this manual removal without significantly increasing the volume required for the support inside the load lock.

After removing the support, it can be carried or stored if desired. The seal 13 maintains a high vacuum in the support during this time, thus minimizing the transport of particulate matter (as well as the adsorption of gas phase contaminants) to the surface of the wafer.

Note that the wafer support also has an elastic element 27 attached to its door. These elastic elements apply light pressure to the wafer 48 when the door 14 is closed, thus restraining the wafer from rattling and generating particulate matter. Although the elastic element 27 is configured as a set of springs in the illustrated embodiment, other mechanical structures (eg, protruding bead edges of the elastic polymer) can be used instead. When the wafer to be used has a flat portion, it is preferable to provide a flat contact surface 29 on the inner rear surface of the wafer support box 10 so that the flat portion of the slice is pressed against each other.

Note that the crosspiece 60 on the side wall of the support box 10 is tapered. This helps ensure that contact with the supported surface of the wafer is made only along the lines, not the actual area. This reduces wafer damage and the generation of particulate matter during transport. Moreover, this is, as mentioned earlier,
Helps eliminate the accumulation of positioning errors.

It is preferable that the lid 20 of the load lock is provided with a window so that the operator can inspect whether or not a mechanical catch has occurred.

An advantage of the present invention is that in the event of various possible mechanical malfunctions, the door of the wafer support 10 can be closed before attempting to remedy the problem. For example, the transfer arm 28 has 3 wafers.
If the wafer is picked up so that it does not sit properly on all of the pins 50, the door drive motor 26 can be activated to close the door 14 before attempting to remedy this problem. Similarly, if the transfer arm 28 can be retracted to a fixed position, the port 30 can be closed. It is possible to remedy such a mechanical out-of-match problem by simply changing the normal control sequence. For example, in some cases, the transfer arm 28 of the wafer 48 on the transfer arm 28 is simply extended halfway so that the edges of the wafer 48 just contact the outside of the isolation gate on the door 14 or port 30. The position can be adjusted. If this does not work, return the load lock 12 to atmospheric pressure (with the door 14 of the wafer support 10 closed), open the load lock lid 20, and then open the load lock lid 20.
The problem can be corrected manually.

Note that all the operations described above can be controlled very easily. That is, it does not require a servo or a complicated negative feedback mechanism. All four motors mentioned above are simple step motors, so that many stations of the present invention can be controlled by a single microcomputer. The mechanical stability of the entire device, i.e., due to the tapered pins on the wafer support.
The inherent correction of small misalignment errors due to the slope of the wafer support rails of the wafer support and due to the flat part of the rear wall of the wafer support helps prevent small errors from accumulating and allows for easy control. To.

This advantage of simplicity of control is in part because good control of mechanical alignment is achieved.
As mentioned earlier, the coalescence of the support 10 with the platform 18 provides one element of mechanical alignment. This is the platform 1 for the transfer arm 28
This is because the position of 8 can be calibrated accurately and permanently. Similarly, the wafer support 10 does not need to be controlled in each dimension, and the support shelves 60 relative to the bottom (or other part) of the box that meets the support platform 18.
All you have to do is control it so that you can know the exact position and orientation of.
As mentioned earlier, this is preferably achieved by providing a groove that slides along the wafer support until it rests on the platform 18, but many other different mechanical devices are used. Can be done.

Similarly, mechanical alignment must be achieved between the home position of the transfer arm 28 and the support pin 50 (or other support form) that coalesces the wafer inside the processing chamber. However, this mechanical matching should be a simple one-time configuration calibration.

As described above, the box itself protects the angular position. When the door 14 is closed, the spring element inside the door 14 presses the wafer 48 against the flat portion on the rear surface inside the box.

By voluntarily selecting, the wafer support 10 can be provided with a fast-connecting vacuum tube joint to perform separate depressurization of the support 10. However, this is omitted in the currently preferred embodiments. That is because it is not necessary, and it can be another cause of reduced reliability.

The load lock mechanism described so far is the most preferred embodiment, but it does not have to be used only for vacuum-dense wafer supports. This load lock can also be used for wafer supports that have atmospheric pressure inside.
This is not the most preferred embodiment, but it still has significant advantages over traditional load locking operations, as mentioned earlier.

Note that the wafer supports mentioned above can be made to different dimensions to support any desired number of wafers. Further, the wafer supports of the present invention can be used to carry or store any desired number of wafers up to the maximum. This gives extra flexibility in terms of planning and process equipment logic.

FIG. 10 shows another embodiment in which two load locks, each having a wafer support 10, are both connected to a process module 102 having four process stations 104. Transfer arm 28
Processes from load lock 12 through port 30
Upon entering module 102, it places the wafer on one of the two wafer stages 106. As mentioned earlier, such a wafer stage 106 may be a support with three pins, a support with two crosspieces, or any other machine considered by one of ordinary skill in the art. However, under the supported wafer, the transfer arm 28 may place the wafer on the support, and then the transfer arm 28 may be lowered to separate from the wafer and retract. There must be space to make it. (However, it is preferable that the wafer support used is in contact with the lower surface of the wafer by line contact rather than over a substantial area.)

A separate transfer arm assembly 106 is provided within the process module. This transfer arm assembly is generally similar to the transfer arm assembly 28, 44, 46 used inside the load lock, with some differences. First, the transfer arm 28 used inside the load lock only needs to move the wafer along a straight line. In contrast, the transfer arm assembly 106 must also be able to move radially in order to select any one process module 104. Therefore, another degree of freedom is required. Second, the range of movement of the transfer arm assembly 106 does not have to be the same as the transfer arm assembly 28, 44, 46 used inside the load lock, and in fact the range of movement of the transfer arm 106 is the process. It is preferable to make the stations even larger so that the stations 104 can be spaced appropriately. Third, the arm assembly 106 does not need to move as large as the transfer arm 28 used in the load lock. Fourth, in the illustrated form, the transfer arm 128 is part 3
One of the pins 50 does not rest on the flat part of the wafer, so they handle wafers of the same diameter,
The diameter of the circle drawn by the pin 50 is not the same for the arms 28 and 128.

Despite these differences, it is preferred that the transfer arm assembly 106 is essentially the same as the transfer arm assembly 28, 44, 46 used within the load lock.
By making the tubular support 46 rotatable and providing a third motor to drive this rotation, the transfer arm 3
The second degree of freedom is obtained. Similarly, the dimensions of the transfer arm can be easily changed as desired. Therefore, it is preferable that the transfer arm assembly 106 includes a transfer arm 128 rotatably mounted on the transfer arm support 144. The transfer arm support 144 is pivotally attached to the tubular support 146 (not shown), and an internal shaft fixed to the transfer arm support 144 extends downward in the tubular support 146. If the internal chain drive with a 2: 1 gear ratio has discriminatory rotation between the tubular support 146 and the arm support 144, then the arm support 144 and the transfer arm 1
Convert to another discriminatory rotation between 28 (over twice the frequency). An arm drive motor mounted below the transport assembly 106 is connected so as to rotate a shaft fixed to the arm support 144. An arm rotation motor is connected to rotate the tubular support 146. Finally, the elevating mechanism causes the transfer arm assembly 106 to move in the vertical direction.

The vertical movement required for the assembly 106 is typically not as great as required for the transfer arm 28 within the load lock 12. This eliminates the need to select one of several vertically separated wafer positions, as the transfer arm 128 is typically within the wafer support 10, and typically simply simply. It is only used to pick up or place wafers from several possible wafer stations, all on the same plane. Therefore, the transfer arm 1 can be selected at will.
The vertical height of the 28 can be controlled by an air cylinder rather than by the elevating motor assembly as described above.

Therefore, by rotating the tubular support 146 at the same time as the arm support 144, the transfer arm assembly 106 can be rotated without extending. After the arm support 106 has rotated to the desired position, the arm support 144 can be rotated while the tubular support 146 remains fixed. This causes the transfer arm 128 to extend as previously described.

Therefore, the wafer to be processed by the transfer arm 28 from one load lock 12 is one wafer.
After placing on stage 106, transfer arm assembly 10
6 can be rotated (if necessary) and extended low so that the transfer arm 128 is below the wafer and raised so that the transfer arm 128 picks up the wafer and retracts it into place. .. The assembly 106 is then rotated again to extend the transfer arm 128 so that the wafer is then above the wafer support at one process station 104 or above the other wafer stage 106. By lowering the arm assembly 106, the wafer is then turned into a wafer support or wafer.
It can be placed on the stage, where the arm 128 can be retracted.

The process station 104 can be sealed from the main process module 102 and a separate single wafer process of the wafer can be initiated. On the other hand, the transfer arms 128 and 28 can perform other operations. When the processing of the wafer in the module 104 is completed, this process station 104 is processed.
The process station 104 can be opened by reducing the pressure to the same low pressure as inside the module 102. At this time, the transfer arm assembly 106 can be operated to take out the wafer and transfer it to one wafer stage 106 or another process module 104.

One advantage of the present invention is that the process modules 104 can all be configured to do the same work. This allows a sufficient number of process stations 104 in the process module 102.
With, the wafer processing volume can be limited by transport (even for fairly slow processing operations), or different process stations 104.
You can do different tasks with.

[0103] That is, the present invention allows for sequential treatment, as it eliminates variations in treatment due to adsorbed contaminants or natural oxides, which is increasingly recognized as desirable. .. For example, two process stations 104, one with a nitride deposit, one
One can be constructed for the growth of oxides in the poly deposit, thus completing the on-site production of oxynitride poly polycapacitors. In addition
Using different process steps for different stations 104 allows the division of multiple lots and processes by programming the appropriate work without relying on the technician to correctly identify which wafer goes into which equipment. It means that you can make changes. For this reason
Being able to allow different tasks to proceed at different process stations provides another flexibility in processing.

It should also be noted that the overall wafer transfer sequence is completely arbitrary and can be selected as desired. For example, the wafer from one wafer support 10 is completely processed, returned to the wafer support 10, and the load lock 12 containing the freshly processed wafer is sealed from the process module 102.
A wafer on another wafer support 10 on another load lock 12 can be processed, while a technician can remove a support full of processed wafers from the other load lock 12. Instead, take advantage of the programming capabilities and random access of this configuration to place the wafer in any form and in any desired form on the two supports 10.
Can be transferred or exchanged between.

[0105] This configuration has two load locks 12, 4 and 4.
No restrictions on one process station 104
Two or more configurations described herein may be in line with another number of process stations 104 in module 102 or in other numbers of load locks 12 mounted on module 102, or optionally inside one module. Note that the transfer arm assembly 106 can be modified so that it can be used.

Note that this configuration leaves the wafer orientation intact. Assuming that the wafer is supported in the support 10 with its flat portion facing the back side of the support 10, the wafer is placed on the wafer stage 106 with its flat portion facing the center of the module 102. Ru. The transfer arm 106 keeps this orientation so that when the flat portion is returned to any wafer support 10, the flat portion of the wafer faces the back of the box.

An embodiment of a group of inventions that implements the ideas described in the other application for another particular case will be described below.

[0108] Note, for example, in FIG. 5 of the other application, the device can be configured to have only one transfer arm instead of three. That is, the wafer support reaches the wafer support directly through the open boat with respect to the central transfer arm 106, and uses the two local transfer arms 28 in the load lock 12. It can be positioned so that the wafer can be taken out without it. The advantage of this scheme is that it eliminates the need for extra mechanisms, controls and vacuum passages to operate the transfer arm 28. The disadvantage is that the transfer arm assembly 106, in turn, must be able to access the entire range of slices stacked in the wafer support 10 as well as picking up and lowering the wafer. The movement of the vertical axis must be increased. Second, the access port 30 must be made larger. That is, the port 30 is a transfer arm assembly 106.
At the height of any wafer within the support 10.
It must have a sufficient vertical range to allow it to pass through. Another drawback is that the transfer arm assembly 106 must extend over a larger physical distance than would otherwise be required. This means that it is more difficult to configure and operate this arm to avoid misalignment. (If the mechanical positioning control device of this device is considered as a control system, the filtering action of the error obtained by the temporary location of the wafer on the stage 105 disappears, and further, it is required for the transfer arm assembly 106 at this time. Longer physical extension means that there is a larger raw error in the position.) Moreover, the device is so modular and cannot be easily expanded. For this reason, examples of these groups are not so preferred at present, but are still a viable group of examples of the invention, which may be considered even more preferred in the future, and for that reason. It is included here for the sake of complete explanation.

Another group of examples uses wafer supports of different shapes. As mentioned in the other application above, various wafer support shapes can be used. Then yet another 1
The shapes of the two wafer supports will be described in detail.

In this form, as shown in FIG. 2, the wafer support 10'instead of having a sealable door 14 that can be opened.
Has an ascending sealing cover 14', which is vacuum sealed 1
It is coupled to the main body of the wafer support by 3'.
In this embodiment, a handle 11'is provided on the top of the cover 14'to transport the aggregate and remove the cover. A latch 15'attached to the substrate 202 is provided to engage the crosspiece 204 at the bottom of the cover, thus attaching the cover to the body of the support 10'whether or not the seal 13'remains tightly in vacuum. Guarantee that it will remain. For this reason
By providing the plate 202 with an extra element called a safety latch 15', the modified wafer support shape 10'can be utilized. (The shape of this modified wafer support is very similar to one conventional device, i.e. sold by VG Systems, Inc.) That is, FIGS. 2-6.
In the embodiment shown in, the basic wafer support commonly used in a conventional device is modified to use such a wafer support in a vacuum processing device as described in another application above. To be able to do it.

Note that on the plate 202, the latch 15'has a boss 206 along its base, which provides a place for the periphery of the boss 204 on the lower edge of the cover 14'.

[0112] In this embodiment, the platform 18'is modified to have a positioning pin 21, one coaxial with the overall cylinder of the wafer support and the second away from the axis. Therefore, the radial orientation of the wafer support can be controlled.

Therefore, in this embodiment, the latch 15'is manually opened and the sealed support assembly 10'is manually placed on the platform 18'. After closing the lid of the load lock and depressurizing the load lock so that the vacuum seal 13'is released, the cover 11'can be separated from the body of the support, and thus inside the body of the support 10'. A wafer can be accessed by the transfer arm 18 as described above.

[0114] A configuration is also conceivable in which the cover is lifted from the main body of the support. However, more preferably, as shown in FIG. 3, the main body 210 of the wafer support 10'is first supported on the stage 212. This stage supports the platform 18'. The stage 212 is then lowered by a mechanical transport element 214, the cover 14'remains supported by the floor 216 above the load lock 12', while the body 210 is the load lock 1
Allow it to be lowered into the lower chamber 218 of 2'.

[0115] In the preferred form of this embodiment, the substrate 202
And the safety catch 15'is used only to transport or store the wafer support outside the load lock chamber and is manually removed from the base of the support 10'before being placed inside the load lock 12'. Be removed. Therefore, in this embodiment,
Dust between the upper chamber 219 and the lower chamber 218 where the cover 14'of the wafer support 10'remains in place in the upper chamber 219 of the load lock and is exposed to particulate matter when the cover 20' is opened. It becomes a barrier to. If the support body 210 is in the lower chamber 218 when the cover 14'is not in place, the stage 212 itself acts as a debris barrier to the partial underside of the floor 216. Further, a vacuum seal 220 can be provided so that the upper chamber 219 itself can be used as the only load lock and the lower chamber 218 can be kept in a vacuum state. This is not always preferable, but it is a voluntary use of this embodiment. In addition, this shape improves debris isolation because the upper chamber 219, which is most directly exposed to debris, has a relatively slight smooth surface, thus making it easier to blow off particulate matter. Will be done. Therefore, in this example, the upper chamber 219 is connected not only to the vacuum port 36'but also to the purge port 22'. When the upper chamber 219 is sealed and the coarse pressure is reduced, purge gas can be passed through port 22'. For example, moist air or partially ionized clean gas at port 22'.
It may be desirable to blow away from the particulate matter to reduce electrostatic adhesion.

[0116] This other embodiment has the additional advantage that the wafer itself does not even see the load lock surface exposed to the particulate matter when loading the support onto the lock. For this reason, the wafer support body and the wafers therein never see not only the dirty surrounding atmosphere, but also the surface exposed to the dirty surrounding atmosphere.

The effectiveness of this debris seal between the cover 14 and the partial floor 216 can be further enhanced by adding another sealing element. For example, a vacuum O-ring can be fitted to the floor 216 so as to surround the opening into which the support body fits and sealed against the smooth surface under the flange of the cover. Although less preferred, another O-ring can be provided on the support cover itself.

In addition, this O-ring and the resulting improved vacuum and debris isolation can be used to allow for another (alternative and optional) mode of operation. The upper chamber is a vacuum seal, whether it is a seal between the lower edge of the wafer support cover and a partial upper floor, or a seal between an elevating stage and a partial upper floor. Even if it is always isolated from the lower chamber, the pressure and cleanliness of the upper chamber is not so critical. In some applications where the processing volume of the loading operation is desired to be improved, it may be desirable not to reduce the pressure of the upper chamber to the low pressure and number of particulate matter required for the actual wafer transfer. For example, in this extreme case, the upper chamber can simply be used as an air shower chamber to remove the rough particulate matter and create an atmosphere comparable to a normal clean room. In another form, if you want to perform very high vacuum work (such as molecular beam epitaxy (MBE)), which typically ^{requires a pressure of 10-10 torr or less, the upper chamber It can be used for coarse depressurization up to about 10-5} torr to reduce the load on the ultra-high vacuum device in the lower chamber.

[0119] In the wafer support of this other embodiment, the crosspiece 60 that supports the wafer is still used, but this time,
As can be seen most clearly in the plan view of FIG. 4, they are arranged as two rows 226 of the side surfaces facing each other, and the wafer holder 224 is supported by line contact.

Note that in this embodiment, the wafer retainer 224 is used instead of the unmounted wafer 48. Although this modification is not particularly advantageous, it provides a different embodiment of the invention that is compatible with other existing processing devices. FIG. 6 is a detailed view showing how the wafer 48 is fixedly held in the wafer holder 224 by the expanding spring 227. In any case, whether a bare wafer or a wafer support is used, the wafer is used to prevent the generation of particulate matter, as described earlier in the other application and specification above. It is desirable to reduce the contact area with. For this reason, it is preferable that the crosspiece 60 that supports the side surface of the wafer 48 (or the wafer holder 224) is tapered for the reason described in the other application.

[0121] In certain embodiments where the wafer holder 224 is used, the wafer holder 224 has a notch 229 that engages the rear support rod 228. This notch helps ensure radial wafer positioning. In other words, when a bare wafer is used, it has the same effect as the flat rear surface of the wafer support 10 which is pressed against the flat portion of the wafer 48.

In this embodiment, the side support columns 226 and the rear support rod 228 are joined at the top by an upper support member 211, which includes an extension of the handle, which has mechanical robustness. The exposed wafer support main body 210 can be operated.

[0123] In this embodiment, the spring 27 that prevents the wafer from rattling during transportation is arranged in the side support column 226 as the spring 27'instead of being arranged in the door 14 as before. The door. This means that more force may be required to remove and restore the wafer in the support, so this extra force can be applied without the wafer slipping off the pins. It may be desirable to make the pins on the transfer arm 28 higher to ensure that.

[0124] As those skilled in the art will appreciate, it should be noted that the present invention can be significantly modified and its scope is limited only by the claims.

[0125] The following sections are further disclosed in connection with the above description.

(1) The support has a wafer support body having a support including a crosspiece tapered to support a flat disk so as to support a flat disk, substantially in line contact and without surface contact. Is continuous as a base, the base having a vacuum seal surrounding the side support, and further having a cover shaped to be combined with the vacuum seal of the wafer support body, the cover, the vacuum seal and the body. Consists of a vacuum-dense outer cover, and the cover is a wafer support that is detachable from the main body in the normal direction with respect to the plane of the vacuum seal.

(2) In the wafer support described in item (1), the wafer support further has a latch plate, and the latch plate includes a latch that holds the cover of the wafer support on the wafer support main body. A wafer support that is detachable from the wafer support and the wafer support main body without disturbing the vacuum sealing between the wafer support and the wafer support main body.

(3) In the wafer support described in (2), the cover is detachable in a substantially normal direction with respect to the direction of one disk limited by the crosspiece of the side support member. A wafer support.

(4) In the wafer support described in (3), a wafer support having a rear support member whose main body has a sloped support surface.

(5) In the wafer support described in (4), the wafer support having a shape in which the wafer support main body limits the mechanical position to the outer surface thereof.

(6) It has a main body including a side wall and a cover that can be sealed together with the main body so as to form a vacuum tight seal, and the side wall limits a groove for holding a wafer having a planned size. It has multiple crosspieces and at least one of the side rails
A wafer support having a gradient on one surface so as to deviate by at least 5 ° from a direction parallel to the plane of the groove.

(7) A main body including a side wall and a cover that can be sealed together with the main body so as to form a vacuum tight seal, each of which limits a groove for holding a wafer having a predetermined size. It has a plurality of crosspieces and at least one of the side wall crosspieces.
One surface has a gradient that deviates by at least 5 ° from the direction parallel to the plane of the groove, and an elastic element is provided on the inner surface of the support, and the elastic element can freely obtain a wafer having a planned size. A wafer support that holds firmly so that it does not move.

(8) The upper chamber has an upper chamber and a lower chamber, a stage that can be raised and lowered, and a transfer arm, and the upper chamber has a lid that can be opened large enough to accommodate a wafer support. The concubine has a partial floor, the floor has an opening, and the floor does not support the body of a wafer support in the form that the floor will have a removable cover that can be vacuum sealed to the body. The cover is supported so that the elevating stage can be translated, and at the limit of one movement, the main body of the wafer support arranged in the opening of the floor of the upper chamber is supported. By moving from the limit of movement of one of them, it is possible to act so as to lower the main body of the wafer support through the opening and into the lower chamber.
At this time, the cover of the wafer support remains supported by the partial floor of the upper chamber, and at least partially between the cover and the partial floor of the upper chamber, and between the upper chamber and the lower chamber. A seal is configured to seal against the particulate matter, and the transfer arm is programmed from the body of the wafer support while the body is placed on the elevating stage below the floor of the upper chamber. A load lock device that is arranged to take out wafers one by one in the possible order.

(9) In the load lock device according to (8), the load lock device in which the upper chamber has an exhaust port.

(10) In the load lock device according to (8), the load lock device in which the upper chamber has a first exhaust port and the lower chamber is connected to a second exhaust port.

In the load lock device according to (11) (8), the upper chamber has both a first exhaust port and a purge port, and the lower chamber is the first exhaust port. A load lock device that has a separate second exhaust port.

[0137] In the load lock device according to (12) (8), when the stage is positioned so as to substantially support the main body of the wafer support arranged in the upper chamber, the above. A load lock device in which the stage creates a vacuum tight seal with the partial floor of the upper chamber.

(13) In the load lock device according to (8), the lower chamber has a transfer arm, and the transfer arm is a wafer arranged on the stage when the stage is lowered. A load lock device that is positioned so as to enter the support body and selectively remove or return the wafer from or within the wafer support body.

[0139] In the load lock device described in (14) and (8), the groove holes of the wafer support are adapted to hold a wafer holder having a predetermined size, and the wafer holder holds the wafer holder having a predetermined size. An integrated circuit load lock device that directly supports a wafer and the transfer arm and the wafer support are in direct contact with the wafer holder instead of the wafer.

(15) In the load lock device described in paragraph (8), the floor of the upper chamber is in close contact with the cover of the support without hindering the movement of the main body of the support. A load-locking device that has a sealed seal that is positioned in, so that the cover acts as a barrier to particulate matter between the upper and lower chambers.

[0141] In the load lock device according to (16) (15), the load lock device in which the seal between the floor of the upper chamber and the cover of the support is vacuum tight.

(17) A plurality of wafers are prepared in a wafer support that can be vacuum-sealed, the wafer support has a cover that is vacuum-sealed in the main body, and the cover is supported in the main body. Vacuum sealed with a partial floor with an opening and a stage placed in close proximity to the floor below the opening, which is detachable from the body in a substantially normal direction with respect to the flat surface of the wafer. The wafer is placed in a possible load lock upper chamber, the load lock upper chamber is ^{depressurized to a pressure of less than 10-4} tolls, the stage is lowered, and the cover covers a partial floor of the upper chamber. An adjacent vacuum-dense space connected to the lower chamber, which remains supported above but allows the body containing the wafer to be lowered into the lower chamber and completes the processing operation in the desired order. One or more selected processes encapsulated inside the
The wafers are transferred from the wafer support to the station in a desired order under vacuum, and then the stage is raised to rejoin the body of the wafer support with the cover of the wafer support in between. A method of manufacturing an integrated circuit including a step of creating a vacuum seal, ventilating the upper chamber to the surroundings, and removing the wafer support from the upper chamber.

[0143] In the method described in paragraph (18) (17), when the stage is substantially in its upper position, the stage creates a vacuum seal between the upper chamber and the lower chamber.
Therefore, a method in which the upper chamber is airtightly sealed from the lower chamber while the wafer support is taken out from the upper chamber or returned to its original position.

[0144] In the method described in (19) (17), the upper chamber has an exhaust and purge port separate from the lower chamber, and is further cleaned before lowering the stage. A method comprising the first step of purging the upper chamber with gas to reduce particulate matter therein.

[0145] In the method described in (20) (17), the exhaust and purge are performed inside the upper chamber when the wafer support is placed therein and the lid of the upper chamber is closed. A method in which only a roughly smooth surface is exposed to the port.

[0146] In the method described in (21) and (17), when the pressure inside the wafer support reseals the main body of the wafer support with the cover of the wafer support, 10
-How to be less than ^{4 torr.}

[0147] In the method described in (22) and (17), the size of the groove of the wafer support is such that a wafer holder having a planned size is held, and the wafer holder holds the wafer holder having a predetermined size. An integrated circuit A method of directly supporting a wafer.

(23) In a method of transporting an integrated circuit wafer during manufacturing, in a vacuum-tight support having a main body including a side wall and a cover that can be sealed together with the main body to form a vacuum-tight seal. Including a step of transporting a wafer in a vacuum state, each of the side walls has a plurality of crosspieces forming groove holes for holding a wafer having a planned size, and at least one surface of the crosspiece of the side wall is the above-mentioned. A method in which a gradient is provided that deviates by at least 5 ° from a direction parallel to the plane of the groove.

(24) In a method of transporting an integrated circuit wafer during manufacturing, it is placed in a vacuum-tight support having a main body including a side wall and a cover that can be sealed together with the main body to form a vacuum-tight seal. Each of the side walls has a plurality of crosspieces that limit the groove holes for holding the wafer having a predetermined size, and at least one surface of the crosspiece of the side wall includes the step of carrying the wafer in a vacuum state. The support is sloped by at least 5 ° from the direction parallel to the plane of the groove, and the support has an elastic element on its inner surface so that the elastic element does not freely move the wafer having the planned dimensions. How to hold it firmly.

(25) The desired manufacturing process is carried out at each of the plurality of process stations separated by an atmosphere of substantially atmospheric pressure, and the integrated circuit wafer manufactured halfway is transported between the process stations. Each wafer includes a step of performing processing steps in a scheduled order, said transport step having a body including the side walls and a cover that can be sealed with the body to create a vacuum tight seal. A step of carrying the wafer in a vacuum state by placing it in a vacuum-dense support is included, and the side wall has a plurality of crosspieces constituting groove holes for holding the wafer having a predetermined size, respectively. The at least one surface of the support is sloped by at least 5 ° from the direction parallel to the plane of the groove, and the support has an elastic element on its inner surface, and the elastic element has the planned dimensions. A method of manufacturing an integrated circuit that firmly holds the wafer to be held so that it does not move freely.

[0151] In the method described in (26) and (25), the size of the groove of the wafer support holds the wafer holder having the planned size, and the wafer holder holds the wafer holder. Integrated Circuit A method of directly supporting a wafer.

(27) A plurality of wafers may be prepared in a wafer support having a cover that can be vacuum-sealed in a main body having a groove for holding the wafer, and vacuum-sealed attached to a process module. The wafer support is placed in the load lock and the load lock is ^{depressurized to a pressure of less than 10-4} tons so that the vacuum seal between the body of the support and the cover of the support is released. The body of the support is removed from the cover while the cover remains in the lock so that the wafer inside the body of the support is within the line-of-sight range of any substantial portion of the interior of the load lock. A transfer arm is placed in the main body of the wafer support, one wafer selected from the transfer arm is taken out from the wafer support, and the wafer support is used until the processing work in the desired order is completed. The wafer is transferred to one or more selected process stations under vacuum and vice versa, after which the wafer support is closed to increase the load lock pressure to approximately atmospheric pressure and thus the wafer. A method of manufacturing an integrated circuit comprising the step of allowing the wafer to remain in a vacuum state within the wafer support while the support is kept closed by differential pressure.

[0153] In the method described in paragraph (28) (27), the transfer arm can be raised and lowered and extended, and the transfer arm has a support element and has a planned diameter.
A method in which one wafer can be supported by the transfer arm only by line contact.

[0154] In the method according to (29) (27), the method of supporting the wafer by the wafer support only by line contact and not in contact with a substantial area of the lower surface of the wafer.

[0155] In the method described in (30) and (27), the size of the groove of the wafer support is such that the wafer holder having the planned size is held, and the wafer holder holds the wafer holder. Integrated Circuit A method of directly supporting a wafer.

[Simple explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the vacuum load lock of the present invention, showing a wafer support of the present invention in the process of loading and unloading.

FIG. 2 illustrates a portion of another embodiment in which a wafer support is configured to have an ascending sealing cover coupled to the body of the wafer support by vacuum sealing instead of a sealable door that can be opened. Is.

FIG. 3 is a diagram showing another part of the above-mentioned other embodiment.

FIG. 4 is a diagram showing still another part of the above-mentioned other embodiment.

FIG. 5 is a diagram showing still another part of the above-mentioned other embodiment.

FIG. 6 is a diagram showing still another part of the above-mentioned other embodiment.

FIG. 7 is a graph showing the time required to fall in the air at various pressures for various dimensions of a particulate matter.

FIG. 8 is a partially cutaway perspective view of an example wafer transfer structure at a processing station showing a wafer placed on three pins by a transfer arm from an adjacent load lock through a port. There is.

FIG. 9 is a detailed view of a wafer support of one embodiment combined with a platform inside a load lock to mechanically align the wafer positions.

FIG. 10 is a plan view of an example processing module including four process stations, two wafer transfer stages and load locks adjacent to each wafer transfer stage.

[Explanation of symbols]

10 Wafer support 12 Vacuum load lock chamber 14 Wafer support door 18 Platform 20 Lid 24 Door opening shaft

────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Robert Alan Bowling Rock Crest Drive 3417 (72) Inventor Timothy A. Garland, Texas, USA. Woold Ritzji, Texas, USA Crestover Circle 402 (72) Inventor Doyuan E. Carter, Plano, Texas, USA Windy Meadow 5005 (72) Inventor Jiyoung E. Spencer Potomac Drive 1401 (72), Plano, Texas, USA Inventor Randall Sea. Hildenbrand Westover, Texas, USA 634

Claims (1)

[Claims] 1. A desired processing step is performed at a plurality of process stations separated by an atmosphere of substantially atmospheric pressure, and an integrated circuit wafer manufactured halfway is transported between the process stations. Including a step of carrying out processing steps in a scheduled order for each wafer, the transporting step puts the wafer into a vacuum-tight support after the wafer has been transported after carrying out the processing step. A method of manufacturing an integrated circuit including a step of inserting and transporting the wafer in a vacuum state.