JP2007088177A - Substrate processing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To take in a clean atmosphere (the air) into a load lock chamber without elongating a processing time by evading the intake of the atmosphere of an infected transfer chamber to a standby chamber concerning a substrate processing system. <P>SOLUTION: The substrate processing system comprises a processing chamber 201 for processing a substrate in the substrate processing system; the standby chamber (the load lock chamber 141) arranged under the processing chamber; the transfer chamber 124 which is arranged adjacent to the standby chamber via a gate valve 143, and to which the substrate is transferred; a guide passage 15 for guiding the air 16 from the outer part of the substrate processing system to the standby chamber (the load lock chamber 141); and in the guide passage a filter (a chemical filter 20) for removing at least organic gas and/or acidic gas and/or alkaline gas, and a filter (a gas filter 30) for removing dust. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a substrate processing apparatus, and in particular, includes an air replacement mechanism that supplies clean air to the standby chamber in order to return the standby chamber below the processing chamber from the inert atmosphere such as N ₂ (nitrogen) to the atmosphere. The present invention relates to a substrate processing apparatus.

  In general, a vertical diffusion / CVD apparatus capable of reducing dust and space is used as a substrate processing apparatus used in a thermal diffusion process and a film formation process in a semiconductor device manufacturing process.

  In this vertical diffusion / CVD apparatus, as shown in FIG. 5, a processing furnace 202 made of a heater, a heat insulating material and the like provided around a cylindrical processing container is provided in a substantially rectangular casing 111. It is provided vertically at the top. A load lock chamber 141 is provided under the processing furnace 202 in the casing 111 as a standby space for waiting for the boat 217 on which a large number of semiconductor wafers to be processed are placed. It can be carried in and out of the heat treatment furnace by elevating means such as a boat elevator.

  Further, a transfer chamber 124 is provided between the load lock chamber 141 and the pod chamber (see the pod chamber 109 in FIG. 2). The pod chamber has a structure including a pod shelf (see the pod shelf 105 in FIG. 3) and the like for receiving and receiving a pod (see pod 110 in FIG. 2) loaded with a wafer and temporarily holding the pod. The transfer chamber 124 includes a wafer transfer mechanism 125 that transfers wafers between the pod in the pod chamber and the boat 217 in the load lock chamber 141. The transfer chamber 124 is configured such that the atmosphere (atmosphere) in the clean room is introduced through the transfer chamber clean unit 134 including the chemical filter 136 and the gas filter 137.

  The transfer chamber 124 and the load lock chamber 141 and the load lock chamber 141 and the processing chamber 201 (processing furnace 202) are airtightly partitioned by gate valves (gate valves) 143 and 147, respectively. It is connected.

  In order to limit the contact of the wafer with cleaning air as much as possible, the atmosphere in the load lock chamber 141 is replaced with nitrogen gas without evacuating the load lock chamber 141.

For example, in Japanese Patent Application Laid-Open No. 2003-92329 (Patent Document 1), an exhaust pipe for exhausting the load lock chamber 141 to less than atmospheric pressure on the bottom wall of the pressure-resistant housing 140 forming the load lock chamber 141, and a load lock An air supply pipe for supplying nitrogen (N ₂ ) gas to the chamber 141 is connected, and in a load-locked state, the load lock chamber 141 is evacuated to a vacuum by an exhaust pipe, and then nitrogen gas is supplied to the air supply pipe The oxygen and moisture inside are removed by evacuation and nitrogen gas purge.
JP2003-92329A (paragraphs 0011 and 0028)

  By the way, the load lock chamber 141 is temporarily returned to the atmosphere when a wafer is loaded and unloaded. That is, in order to process the wafer in the processing chamber 201, the wafer is transferred from the pod of the pod chamber to the boat 217 via the wafer transfer mechanism 125. At this time, in order to release the gate valve 143, a load lock is performed. The chamber 141 is once returned to the atmosphere.

After the wafer is transferred, the gate valve 143 of the load lock chamber 141 is closed and evacuation is performed by an evacuation apparatus, and at the same time, nitrogen (N ₂ ) gas is introduced to replace the atmosphere of the load lock chamber 141. Thus, after reducing the concentration of oxygen, moisture, etc., the furnace port gate valve 147 is opened, and the wafer is transferred into the processing chamber 201 together with the boat 217. Due to N ₂ substitution, the oxygen concentration becomes 1 ppm or less in a relatively short time.

After the wafer processed in the processing furnace 202 is taken out from the processing chamber 201 into the load lock chamber 141, the load lock chamber 141 in the N ₂ atmosphere (oxygen concentration of 1 ppm or less) is in an atmospheric state (oxygen concentration of about 18%). Return to. At that time, conventionally, by opening the gate valve (commonly referred to as LGV) 143 of the load lock chamber 141, the atmosphere (oxygen) in the transfer chamber 124 is taken into the load lock chamber 141 and oxygen is supplied.

  However, under this atmosphere replacement mechanism, the atmosphere through the clean unit 134 installed in the transfer chamber 124 is taken into the load lock chamber 141. That is, acid / alkaline / organic gas components are removed by the chemical filter 136 on the upstream side (primary side) of the clean unit 134, and then dust is collected by the gas filter 137 including a Teflon filter built in the clean unit 134. Clean air (oxygen) from which (particles) have been removed passes through the transfer chamber 124 and is taken into the load lock chamber 141.

  However, in the transfer chamber 124, a transfer system unit having a linear movement shaft such as a ball screw / linear shaft coated with grease is installed, and components that generate organic gas (packing with adhesive, Various cable protecting vinyls, etc.) exist, and the atmosphere in the transfer chamber 124 is contaminated by dust generation from these. Accordingly, when the contaminated atmosphere in the transfer chamber 124 is taken into the load lock chamber 141, the atmosphere in the load lock chamber 141 and the wafer are also contaminated.

In the apparatus in which the inside of the transfer chamber 124 is also managed in the N ₂ atmosphere, the inside of the transfer chamber 124 is once returned to the atmosphere, and then the atmosphere (oxygen) is transferred from the transfer chamber 124 into the load lock chamber 141. Incorporation requires that the atmosphere in the transfer chamber 124 be returned to the atmospheric atmosphere once, and there is a problem that the time from carrying in the pod to carrying out becomes so-called “tact extension”.

  Accordingly, an object of the present invention is to solve the above-mentioned problems, avoid taking a contaminated transfer chamber atmosphere into the standby chamber, and load lock a clean atmosphere (atmosphere) without tact extension. An object of the present invention is to provide a substrate processing apparatus provided with an atmospheric substitution mechanism that can be taken into a room.

  A substrate processing apparatus according to the present invention includes a processing chamber for processing a substrate in the substrate processing apparatus, a standby chamber disposed below the processing chamber, and the standby chamber being adjacent to the standby chamber via a gate valve to transfer the substrate. A transfer chamber, an introduction path for introducing air into the standby chamber from outside the substrate processing apparatus, and at least an organic gas and / or an acid gas and / or an alkaline gas removal filter and a dust filter in the introduction path. It is characterized by providing.

  The substrate processing apparatus of the present invention includes the following aspects.

(1) Acid / alkaline / organic gas body removal as an air introduction path for returning the load lock chamber under the N ₂ atmosphere to the atmospheric state (oxygen concentration 18% or predetermined oxygen concentration level state) Supply system piping equipment equipped with the intended chemical filter and gas filter for the purpose of dust (particle) removal will be installed.

  (2) Air or dry air is supplied to the standby chamber, that is, the load lock chamber (standby chamber) or the space where the wafer exists (standby space) through the supply system piping facility.

  (3) A vacuum pump is used as a suction method (exhaust method) when air or dry air is supplied to the load lock chamber (standby chamber) or the space where the wafer exists (standby space) through the supply system piping facility. .

According to the present invention, the atmosphere is introduced from the outside of the substrate processing apparatus through the introduction path, and is guided to the standby chamber through the organic substance removal filter and the dust filter, so that clean atmosphere (oxygen) is taken in and the standby chamber is filled with the N ₂ atmosphere ( It is possible to return from the oxygen concentration of 1 ppm or less to the atmosphere (oxygen concentration of about 18%).

Further, according to the present invention, even if the transfer chamber 124 is also managed in an N ₂ atmosphere, the transfer chamber 124 can be moved from the transfer chamber 124 to the atmosphere without having to return to the atmosphere once. Since (oxygen) can be taken into the load lock chamber 141, tact stretching can be avoided.

  In addition, it is possible to improve the performance by simply adding parts necessary for the application without changing the standard configuration of the existing apparatus. For example, when it is desired to increase the air introduction amount, it can be achieved only by adding a branch port and increasing the number of pipes constituting the air introduction path. In addition, when it is desired to remove moisture contained in the atmosphere, a drier filled with activated carbon such as purifier may be added in the middle of the piping of the air introduction path.

  Hereinafter, the present invention will be described based on the illustrated embodiments.

  FIG. 1 is a schematic view of a vertical diffusion / CVD apparatus according to the present invention, and the presupposed structure is basically the same as that of the conventional (FIG. 5). That is, a processing furnace 202 made of a heater, a heat insulating material, and the like provided so as to surround a cylindrical processing container is provided vertically at an upper portion in a substantially rectangular casing 111. A load lock chamber 141 is provided under the processing furnace 202 in the casing 111 as a standby space for waiting for the boat 217 on which a large number of semiconductor wafers to be processed are placed. It can be carried into and out of the heat treatment furnace 202 by lifting means such as a boat elevator. Further, in the transfer chamber 124 adjacent to the load lock chamber 141, a wafer transfer mechanism for transferring wafers between the pod 110 in the pod chamber 109 and the boat 217 in the load lock chamber 141 shown in FIG. 125 is provided. The transfer chamber 124 and the load lock chamber 141 are connected via a gate valve 143, and the load lock chamber 141 and the processing chamber 201 (processing furnace 202) are connected via a gate valve 147. .

  However, it differs from the prior art (FIG. 5) as follows.

  In FIG. 1, the atmosphere introduction port 10 is formed at a position away from the processing furnace 202 on the front side of the case 111 in the upper part of the case 111, and the transfer chamber 124 is introduced from here through the branch port 11. An air introduction duct 12 is disposed up to the mouth 14. The air introduction port 10 is provided with a chemical filter 10 for the purpose of removing acid / alkaline / organic gas bodies, and the clean air 13 that has passed therethrough passes through the air introduction duct 12 and enters the introduction port. 14 is introduced into the transfer chamber 124. A transfer chamber clean unit 134 having only a gas filter 137 is provided at the introduction port 14 of the transfer chamber 124, and the atmosphere (air) in the clean room is introduced through the gas filter 137. Yes.

  In this way, an atmosphere introduction path is formed from the atmosphere introduction port 10 to the load lock chamber 141. Of these, the chemical filter 10 to the transfer chamber clean unit 34 are formed by a clean stainless steel duct. It is connected and sent as clean air.

  On the other hand, the introduction path for introducing the atmosphere from the outside of the substrate processing apparatus to the load lock chamber 141 as a standby chamber is configured as follows.

  The branch port 11 provided in the atmosphere introduction port 10 is provided with an atmosphere introduction pipe 15 toward the load lock chamber 141, and the introduction provided in the lower part of the pressure-resistant housing 140 forming the load lock chamber 141 by the atmosphere introduction pipe 15. Connect to mouth 18. For the air introduction pipe 15, a pipe whose inner surface is clean, for example, a stainless steel or Teflon (registered trademark) pipe whose inner surface is polished is used. As a method of piping the atmosphere introduction pipe 15, the atmosphere introduction pipe 15 is led from the front side of the casing 111 to the back side beyond the processing furnace 202 through the upper part in the casing 111, and further to the casing 111. It arrange | positions so that it may guide | lead to the inlet 18 of the lower part of the pressure | voltage resistant housing | casing 140 along an inner back wall.

  A gas filter 30 and an on-off valve 17 for the purpose of removing dust (particles) are provided near the inlet 18 in the middle of the connecting pipe of the air introduction pipe 15. As a result, the atmosphere introduction path from the atmosphere introduction port 10 to the load lock chamber 141 is in the middle of the organic gas or / or acid gas or / or alkaline gas removal filter composed of at least the chemical filter 20 and the gas. A dust removal filter composed of the filter 30 is provided. An exhaust pipe 145 that continues to the vacuum pump is connected to one end of the pressure-resistant housing 140 that forms the load lock chamber 141.

  As the medium (collecting member) of the gas filter 30, a medium made of stainless steel, nickel, or Teflon (registered trademark) can be used. Further, as the performance of the gas filter 30, it is preferable that the flow rate can be increased as much as possible in order to shorten the time required for heat substitution. The volume of the load lock chamber 141 is 916 liters, the diameter of the air introduction pipe 15 is about 12.7 cm (1/2 inch), and the performance of the gas filter 30 is a flow rate of 500 L / min or more at a differential pressure of 5 kPa. It is optimal to use a gas filter that has a performance of collecting, for example, “99.9999999% or more of particles of 0.003 μm or more” as the collection efficiency. However, the specific appropriate performance is determined by the application (process) of the load lock chamber.

  As described above, an air introduction path is formed in which acid / alkaline / organic gas bodies are removed through the chemical filter 20 and dust (particles) are removed through the gas filter 30. Then, air (or dry air) is supplied from this air introduction path, which is sucked by the exhaust of the vacuum pump connected to the exhaust pipe 145 of the load lock chamber 141 or uses the pressurization from the upstream. This is done by supplying air (or dry air). At this time, since the supplied air does not pass through the transfer chamber 124 provided with the wafer transfer mechanism 125 as in the prior art, clean air 16 that is not contaminated is supplied to the load lock chamber 141.

Therefore, when the inside of the load lock chamber 141 is returned from the inert atmosphere state such as N ₂ (nitrogen) to the atmosphere (oxygen concentration of about 18%), the clean atmosphere 16 that does not pass through the transfer chamber 124 is transferred into the load lock chamber 141. Can be supplied to.

  In this embodiment, it is configured to have only one atmosphere introduction pipe 15, but when it is desired to increase the amount of introduction of atmosphere, the branch port 11 is added to increase the number of atmosphere introduction pipes 15 constituting the atmosphere introduction path. Can do.

  Further, in this embodiment, only the chemical filter 20 and the gas filter 30 are provided in the middle of the air introduction pipe 15, but when it is desired to remove moisture contained in the air, a dryer filled with activated carbon such as purifier or the like. Can be added in the middle of the air introduction pipe 15.

  Next, the substrate processing apparatus of the present invention will be described in more specific examples. FIG. 2 is a plan perspective view of the vertical diffusion / CVD apparatus according to this embodiment, and FIG. 3 is a side perspective view thereof. In the batch type CVD apparatus 1, a FOUP (front opening unified pod) is used as a carrier for transferring wafers.

  As shown in FIGS. 2 and 3, the substrate processing apparatus 100 of the present invention in which a pod (substrate container) 110 is used as a wafer carrier storing a wafer (substrate) 200 made of silicon or the like includes a casing 111. I have. A front maintenance port 103 as an opening provided for maintenance is opened at the front front portion of the front wall 111a of the casing 111, and front maintenance doors 104 and 104 for opening and closing the front maintenance port 103 are respectively built. It is attached.

  A pod loading / unloading port (substrate container loading / unloading port) 112 is opened on the front wall 111a of the casing 111 so as to communicate with the inside and outside of the casing 111. The loading / unloading opening / closing mechanism 113 is opened and closed. A load port (substrate container delivery table) 114 is installed in front of the front side of the pod loading / unloading port 112, and the load port 114 is configured so that the pod 110 is placed and aligned. The pod 110 is carried onto the load port 114 by an in-process carrying device (not shown), and is also carried out from the load port 114.

  A rotary pod shelf (substrate container mounting shelf) 105 is installed at an upper portion of the casing 111 in a substantially central portion in the front-rear direction. The rotary pod shelf 105 stores a plurality of pods 110. It is configured. That is, the rotary pod shelf 105 is vertically arranged and intermittently rotated in a horizontal plane, and a plurality of shelf plates (substrate container mounts) radially supported by the column 116 at each of the four upper and lower positions. And a plurality of shelf plates 117 are configured to hold the pods 110 in a state where a plurality of pods 110 are respectively placed.

  A pod transfer device (substrate container transfer device) 118 is installed between the load port 114 and the rotary pod shelf 105 in the housing 111, and the pod transfer device 118 moves up and down while holding the pod 110. A pod elevator (substrate container lifting mechanism) 118a and a pod transfer mechanism (substrate container transfer mechanism) 118b as a transfer mechanism are configured. The pod transfer device 118 includes a pod elevator 118a and a pod transfer mechanism 118b. The pod 110 is transported between the load port 114, the rotary pod shelf 105, and the pod opener (substrate container lid opening / closing mechanism) 121 by continuous operation.

  A sub-housing 119 is constructed across the rear end of the lower portion of the housing 111 at a substantially central portion in the front-rear direction. A pair of wafer loading / unloading ports (substrate loading / unloading ports) 120 for loading / unloading the wafer 200 into / from the sub-casing 119 are arranged on the front wall 119a of the sub-casing 119 in two vertical stages. A pair of pod openers 121 and 121 are installed at the wafer loading / unloading ports 120 and 120 at the upper and lower stages, respectively.

  The pod opener 121 includes mounting bases 122 and 122 on which the pod 110 is placed, and cap attaching / detaching mechanisms (lid attaching / detaching mechanisms) 123 and 123 for attaching and detaching caps (lids) of the pod 110. The pod opener 121 is configured to open and close the wafer loading / unloading port of the pod 110 by attaching / detaching the cap of the pod 110 placed on the placing table 122 by the cap attaching / detaching mechanism 123.

  The sub-housing 119 constitutes a transfer chamber 124 that is fluidly isolated from the installation space of the pod transfer device 118 and the rotary pod shelf 105. A wafer transfer mechanism (substrate transfer mechanism) 125 is installed in the front region of the transfer chamber 124, and the wafer transfer mechanism 125 rotates the wafer 200 in the horizontal direction or can move the wafer 200 in the horizontal direction. Substrate transfer device) 125a and wafer transfer device elevator (substrate transfer device lifting mechanism) 125b for raising and lowering wafer transfer device 125a. By the continuous operation of the wafer transfer device elevator 125b and the wafer transfer device 125a, the tweezer (substrate holder) 125c of the wafer transfer device 125a is used as a placement portion for the wafer 200 with respect to the boat (substrate holder) 217. The wafer 200 is loaded (charged) and unloaded (discharged).

  As shown in FIG. 2, a supply fan is provided so that a clean atmosphere or an inert gas clean air 33 is supplied to the right end of the transfer chamber 124 opposite to the wafer transfer apparatus elevator 125b side. And a clean unit 34 composed of a dust filter, and a notch aligner 135 as a substrate aligner for aligning the circumferential position of the wafer between the wafer transfer device 125a and the clean unit 34. Is installed.

  Clean air is introduced into the clean unit 34 through the air introduction duct 13 described with reference to FIG. 1, and the clean air 33 blown out from the clean unit 34 is distributed to the notch alignment device 135 and the wafer transfer device 125a. The air is sucked in by a duct (not shown) and exhausted to the outside of the casing 111 or is circulated to the primary side (supply side) that is the suction side of the clean unit 134, and is again transferred by the clean unit 134 to the transfer chamber 124. It is configured to be blown into the inside.

  In the rear region of the transfer chamber 124, a pressure-resistant housing 140 having a confidential performance capable of maintaining a pressure lower than atmospheric pressure (hereinafter referred to as negative pressure) is installed. A load lock chamber 141 which is a load lock type standby chamber having a volume capable of storing the load lock chamber 141 is formed.

  A wafer loading / unloading opening (substrate loading / unloading opening) 142 is opened on the front wall 140a of the pressure-resistant housing 140, and the wafer loading / unloading opening 142 is opened and closed by a gate valve 143. A gas supply pipe 144 for supplying nitrogen gas to the load lock chamber 141, the air introduction pipe 15 described in FIG. 1, and the load lock chamber 141 are exhausted to a negative pressure on a pair of side walls of the pressure-resistant housing 140. And an exhaust pipe 145 are connected to each other.

In addition, the side wall of the pressure-resistant housing 140 is connected to the air introduction pipe 15 including the chemical filter 20 and the gas filter 30 described with reference to FIG. 1 in order to introduce the atmosphere into the load lock chamber 141, and the load lock chamber 141. By sucking and exhausting with a vacuum pump connected to the exhaust pipe 145, clean air 16 or dry air can be introduced from the air introduction pipe 15. Therefore, when the inside of the load lock chamber 141 is returned from the inert atmosphere state such as N ₂ (nitrogen) to the atmosphere (oxygen concentration of about 18%), the clean atmosphere 16 that does not pass through the transfer chamber 124 is transferred into the load lock chamber 141. Can be supplied to.

  A processing furnace 202 is provided above the load lock chamber 141. The lower end portion of the processing furnace 202 is configured to be opened and closed by a furnace port gate valve (furnace port opening / closing mechanism) 147. A furnace port gate valve cover 149 that accommodates the furnace port gate valve 147 when the lower end portion of the processing furnace 202 is opened is attached to the upper end portion of the front wall 140 a of the pressure-resistant housing 140.

  As shown in FIG. 2, a boat elevator (substrate holder lifting mechanism) 115 for raising and lowering the boat 217 is installed in the pressure-resistant housing 140. A seal cap 219 serving as a lid is horizontally installed on an arm 128 serving as a connector connected to the boat elevator 115, and the seal cap 219 supports the boat 217 vertically and closes the lower end of the processing furnace 202. It is configured as possible. The boat elevator 115 and the arm 128 are housed in a bellows or the like and are provided separately from the load lock chamber 141 so as not to generate organic gas in the load lock chamber 141.

  The boat 217 includes a plurality of holding members so that a plurality of (for example, about 50 to 125) wafers 200 are horizontally held in a state where their centers are aligned in the vertical direction. It is configured.

  FIG. 4 shows a schematic configuration of the processing furnace 202.

  As shown in FIG. 4, the processing furnace 202 includes a heater 206 as a heating mechanism. The heater 206 has a cylindrical shape and is vertically installed by being supported by a heater base 251 as a holding plate.

A process tube 203 as a reaction tube is disposed inside the heater 206 concentrically with the heater 206. The process tube 203 includes an inner tube 204 as an internal reaction tube and an outer tube 205 as an external reaction tube provided on the outer side thereof. The inner tube 204 is made of a heat-resistant material such as quartz (SiO ₂ ) or silicon carbide (SiC), and is formed in a cylindrical shape having upper and lower ends opened. A processing chamber 201 is formed in the cylindrical hollow portion of the inner tube 204, and is configured so that wafers 200 as substrates can be accommodated in a state of being aligned in multiple stages in a horizontal posture and in a vertical direction by a boat 217 described later. The outer tube 205 is made of a heat-resistant material such as quartz or silicon carbide, and is formed in a cylindrical shape having an inner diameter larger than the outer diameter of the inner tube 204 and closed at the upper end and opened at the lower end. It is provided in the shape.

  A manifold 209 is disposed below the outer tube 205 concentrically with the outer tube 205. The manifold 209 is made of, for example, stainless steel and is formed in a cylindrical shape with an upper end and a lower end opened. The manifold 209 is engaged with the inner tube 204 and the outer tube 205, and is provided so as to support them. An O-ring 220a as a seal member is provided between the manifold 209 and the outer tube 205. By supporting the manifold 209 on the heater base 251, the process tube 203 is installed vertically. A process vessel is formed by the process tube 203 and the manifold 209.

  A nozzle 230 as a gas introduction unit is connected to a seal cap 219 described later so as to communicate with the inside of the processing chamber 201, and a gas supply pipe 232 is connected to the nozzle 230. A processing gas supply source and an inert gas supply source (not shown) are connected to an upstream side of the gas supply pipe 232 opposite to the connection side with the nozzle 230 via an MFC (mass flow controller) 241 as a gas flow rate controller. Has been. A gas flow rate control unit 235 is electrically connected to the MFC 241 and is configured to control at a desired timing so that the flow rate of the supplied gas becomes a desired amount.

  The manifold 209 is provided with an exhaust pipe 231 that exhausts the atmosphere in the processing chamber 201. The exhaust pipe 231 is disposed at the lower end portion of the cylindrical space 250 formed by the gap between the inner tube 204 and the outer tube 205 and communicates with the cylindrical space 250. A vacuum exhaust device 246 such as a vacuum pump is connected to the downstream side of the exhaust pipe 231 opposite to the connection side with the manifold 209 via a pressure sensor 245 and a pressure regulator 242 as pressure detectors. The chamber 201 is configured to be evacuated so that the pressure in the chamber 201 becomes a predetermined pressure (degree of vacuum). A pressure controller 236 is electrically connected to the pressure regulator 242 and the pressure sensor 245, and the pressure controller 236 uses the pressure regulator 242 to adjust the pressure inside the processing chamber 201 based on the pressure detected by the pressure sensor 245. Control is performed at a desired timing so that the pressure becomes a desired pressure.

  Below the manifold 209, a seal cap 219 is provided as a furnace port lid that can airtightly close the lower end opening of the manifold 209. The seal cap 219 is brought into contact with the lower end of the manifold 209 from the lower side in the vertical direction. The seal cap 219 is made of a metal such as stainless steel and has a disk shape. On the upper surface of the seal cap 219, an O-ring 220b is provided as a seal member that contacts the lower end of the manifold 209. A rotation mechanism 254 for rotating the boat is installed on the side of the seal cap 219 opposite to the processing chamber 201. A rotation shaft 255 of the rotation mechanism 254 passes through the seal cap 219 and is connected to a boat 217 described later, and is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be lifted vertically by a boat elevator 115 as a lifting mechanism vertically installed outside the process tube 203, and thereby the boat 217 is carried into and out of the processing chamber 201. Is possible. A drive control unit 237 is electrically connected to the rotation mechanism 254 and the boat elevator 115, and is configured to control at a desired timing so as to perform a desired operation.

  The boat 217 serving as a substrate holder is made of a heat-resistant material such as quartz or silicon carbide, and is configured to hold a plurality of wafers 200 in a horizontal posture and in a state where the centers are aligned with each other and held in multiple stages. ing. A plurality of heat insulating plates 216 as a disk-shaped heat insulating member made of a heat resistant material such as quartz or silicon carbide are arranged in a multi-stage in a horizontal posture at the lower part of the boat 217, and the heat from the heater 206 is arranged. Is difficult to be transmitted to the manifold 209 side.

  A temperature sensor 263 is installed in the process tube 203 as a temperature detector. A temperature control unit 238 is electrically connected to the heater 206 and the temperature sensor 263, and the temperature in the processing chamber 201 is adjusted by adjusting the power supply to the heater 206 based on the temperature information detected by the temperature sensor 263. Is controlled at a desired timing so as to have a desired temperature distribution.

  The gas flow rate control unit 235, the pressure control unit 236, the drive control unit 237, and the temperature control unit 238 also constitute an operation unit and an input / output unit, and are electrically connected to a main control unit 239 that controls the entire substrate processing apparatus. ing. These gas flow rate control unit 235, pressure control unit 236, drive control unit 237, temperature control unit 238, and main control unit 239 are configured as a controller 240.

  Next, the operation of the processing apparatus of the present invention will be described.

  As shown in FIGS. 2 and 3, when the pod 110 is supplied to the load port 114, the pod loading / unloading port 112 is opened by the front shutter 113, and the pod 110 on the load port 114 is enclosed by the pod transfer device 118. It is carried into the body 111 from the pod loading / unloading port 112.

  The loaded pod 110 is automatically transported and delivered by the pod transport device 118 to the designated shelf 117 of the rotary pod shelf 105, temporarily stored, and then one pod opener from the shelf 117. It is conveyed to 121 and transferred to the mounting table 122, or directly transferred to the pod opener 121 and transferred to the mounting table 122. At this time, the wafer loading / unloading port 120 of the pod opener 121 is closed by the cap attaching / detaching mechanism 123, and the transfer chamber 124 is filled with clean air 33. For example, the transfer chamber 124 is filled with nitrogen gas as the clean air 33, so that the oxygen concentration is set to 20 ppm or less, which is much lower than the oxygen concentration inside the casing 111 (atmosphere).

  The pod 110 mounted on the mounting table 122 has its opening-side end face pressed against the opening edge of the wafer loading / unloading port 120 on the front wall 119a of the sub-housing 119, and the cap is removed by the cap attaching / detaching mechanism 123. The wafer loading / unloading port of the pod 110 is opened. Further, when the wafer loading / unloading opening 142 of the load lock chamber 141 whose interior is previously set at atmospheric pressure is opened by the operation of the gate valve 143, the wafer 200 is removed from the pod 110 by the tweezer 125c of the wafer transfer device 125a. After being picked up through the loading / unloading port and aligned with the notch aligner 135, the wafer is loaded into the load lock chamber 141 through the wafer loading / unloading opening 142, transferred to the boat 217, and loaded (wafer charging). The wafer transfer device 125 a that has transferred the wafer 200 to the boat 217 returns to the pod 110 and loads the next wafer 200 into the boat 217.

  During the loading operation of wafers into the boat 217 by the wafer transfer device 125a in one (upper or lower) pod opener 121, the other (lower or upper) pod opener 121 has a rotary pod shelf 105 or load port 114. The other pod 110 is transported by the pod transport device 118, and the opening operation of the pod 110 by the pod opener 121 proceeds simultaneously.

  When a predetermined number of wafers 200 are loaded into the boat 217, the wafer loading / unloading opening 142 is closed by the gate valve 143, and the load lock chamber 141 is evacuated from the exhaust pipe 145 to be decompressed.

  When the load lock chamber 141 is reduced to the same pressure as that in the processing furnace 202, the lower end portion of the processing furnace 202 is opened by the furnace port gate valve 147. At this time, the furnace port gate valve 147 is carried into and stored in the furnace port gate valve cover 149.

  Subsequently, the seal cap 219 is lifted by the lift of the boat elevator 115, and the boat 217 supported by the seal cap 219 is loaded into the processing furnace 202.

  After loading, arbitrary processing is performed on the wafer 200 in the processing furnace 202. Here, a case where a thin film is formed on the wafer 200 by a CVD method will be described.

  The operation of each part constituting the substrate processing apparatus is controlled by the controller 240 in FIG. When a plurality of wafers 200 are loaded into the boat 217 (wafer charge), as shown in FIG. 4, the boat 217 holding the plurality of wafers 200 is lifted by the boat elevator 115 and loaded into the processing chamber 201 ( Boat loading). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

  The processing chamber 201 is evacuated by a vacuum evacuation device 246 so that a desired pressure (degree of vacuum) is obtained. At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the pressure regulator 242 is feedback-controlled based on the measured pressure. In addition, the inside of the processing chamber 201 is heated by the heater 206 so as to have a desired temperature. At this time, the power supply to the heater 206 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the inside of the processing chamber 201 has a desired temperature distribution. Subsequently, the wafer 200 is rotated by rotating the boat 217 by the rotation mechanism 254.

  Next, the gas supplied from the processing gas supply source and controlled to have a desired flow rate by the MFC 241 is introduced into the processing chamber 201 from the nozzle 230 through the gas supply pipe 232. The introduced gas rises in the processing chamber 201, flows out from the upper end opening of the inner tube 204 into the cylindrical space 250, and is exhausted from the exhaust pipe 231. The gas comes into contact with the surface of the wafer 200 when passing through the processing chamber 201, and at this time, a thin film is deposited on the surface of the wafer 200 by a thermal CVD reaction.

When a preset processing time has passed, an inert gas is supplied from an inert gas supply source, the inside of the processing chamber 201 is replaced with an inert gas, and the pressure in the processing chamber 201 is returned to normal pressure. . At the same time, the opening / closing valve 17 of the air introduction pipe 15 shown in FIG. 1 is opened, clean air 16 is supplied into the load lock chamber 141, and the load lock chamber 141 has an inert atmosphere such as N ₂ (nitrogen). The state is returned to the atmosphere (oxygen concentration of about 18%). The clean air 16 used here is clean air that does not pass through the transfer chamber 124, and the atmosphere in the load lock chamber 141 is not contaminated as in the prior art.

Thereafter, the seal cap 219 is lowered by the boat elevator 115 to open the lower end of the manifold 209 and the boat 217 is carried out (boat unloading) to the load lock chamber 140 by the boat elevator 115.
Preferably, the boat unloading is performed when the temperature of the wafer 200 is higher than normal temperature (25 ° C.) and not higher than 400 ° C. By doing so, an oxide film can be formed on the heat-treated wafer 200 in a clean atmosphere.

  When the boat 217 is pulled out by the boat elevator 115,

  After the inside of the load lock chamber 140 is restored to the atmospheric pressure as described above, the gate valve 143 is opened. Thereafter, the wafer 200 and the pod 110 are discharged to the outside of the housing 111 in the reverse procedure described above except for the wafer alignment process in the notch aligning device 135.

In the above embodiment, a general description is given of the case where a thin film is formed on the wafer 200 by the CVD method. However, the present invention is particularly effective in forming an oxide film after the PH ₃ annealing process as described below. is there.

PH ₃ gas is introduced from the gas supply pipe 232 in the processing chamber 201, and the substrate is subjected to PH ₃ annealing while maintaining a desired temperature and pressure, thereby doping the wafer (substrate) with P (phosphorus). Prior to unloading the wafer, a chemical filter 20 for removing an organic gas, an acid gas, and / or an alkaline gas from a clean room and an atmosphere are introduced into a load lock chamber 141 that has been in a vacuum state in advance. Air is introduced through the pipe 15 and the gas filter 30 as a dustproof filter. At the same time, after the PH ₃ annealing treatment, the inside of the processing chamber 201 is replaced with an inert gas, and the pressure is returned to normal pressure. When the load lock chamber 141 returns to atmospheric pressure by introducing the atmosphere, the wafer after the PH ₃ annealing process is unloaded from the processing chamber 201. At that time, an oxide film can be formed on the wafer as a protective film by reaction with the atmosphere. Thereby, when pure oxygen is introduced, for example, since there is only about 10 ppm of moisture, the phosphorus concentration of the wafer is difficult to stabilize, whereas about 0.5 to 3% of moisture contained in the clean room air, The phosphorus concentration of the wafer can be stabilized. Further, by forming the oxide film as a protective film, it is possible to prevent phosphorus after phosphorus doping from being released.

It is a figure which shows the outline | summary of a structure of the substrate processing apparatus of this invention. 1 is a plan perspective view of a vertical diffusion / CVD apparatus according to an embodiment of the present invention. FIG. 3 is a side perspective view along line III-III of the vertical diffusion / CVD apparatus shown in FIG. 2. It is a longitudinal cross-sectional view which shows schematic structure of the processing furnace in the vertical type | mold diffusion / CVD apparatus which concerns on the Example of this invention. It is a figure which shows the outline | summary of a structure of the conventional substrate processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Atmospheric inlet chemical filter 11 Branch port 12 Atmospheric inlet duct 13 Clean air 14 Inlet 15 Atmospheric inlet piping 16 Clean air 17 On-off valve 18 Inlet 20 Chemical filter 34 Clean unit 30 Gas filter 124 Transfer chamber 125 Wafer transfer Mechanism 128 Arm 133 Clean air 134 Clean unit 135 Notch aligner 136 Chemical filter 137 Gas filter 141 Load lock chamber 143 Gate valve 145 Exhaust pipe 147 Furnace gate valve 201 Processing chamber 202 Processing furnace 217 Boat

Claims (1)

A processing chamber for processing a substrate in the substrate processing apparatus;
A standby chamber disposed below the processing chamber;
A transfer chamber which is adjacent to the standby chamber via a gate valve and in which the substrate is transferred;
An introduction path for introducing air into the standby chamber from outside the substrate processing apparatus;
A substrate processing apparatus comprising at least an organic gas, an acid gas, or an alkaline gas removing filter and a dust removing filter in the introduction path.

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