KR20130016359A - Substrate processing method and substrate processing system - Google Patents

Abstract

There is provided a substrate processing method and a substrate processing system which can prevent organic contamination of the substrate K in the load lock chamber 10 at a low cost and can more completely prevent it. After storing the plurality of substrates (K) in the cassette (80) and stored in the load lock chamber 10, the preparation process for reducing the pressure while supplying the purge gas and in the transfer chamber connected to the load lock chamber (10) The substrate K in the cassette 80 is taken out by the conveyance mechanism, conveyed to the processing chamber to process the substrate K, and the substrate after processing is taken out of the processing chamber to loadlock. It consists of a process process accommodated in the cassette 80 in the chamber 10. As shown in FIG. In the preparation step, the supply position of the purge gas is provided above the cassette 80, and the exhaust position is provided below the cassette 80, and the cassette 80 is placed between the supply position and the exhaust position. The entire upper surface of the uppermost target substrate K accommodated in the cassette 80 is covered with a cover provided above. In the preparation step, when the pressure in the load lock chamber 10 becomes the first reference pressure, the supply and the exhaust of the purge gas into the load lock chamber 10 are stopped, and when the second reference pressure is reached, Supply and exhaust of the purge gas into the load lock chamber 10 are resumed.

Description

Substrate processing method and substrate processing system {SUBSTRATE PROCESSING METHOD AND SUBSTRATE PROCESSING SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing method and a substrate processing system for processing a substrate under reduced pressure, and more particularly, to a substrate processing method and a substrate processing system for allowing a substrate to be processed to stand in a load lock chamber under reduced pressure.

As said substrate processing system, what was disclosed by Unexamined-Japanese-Patent No. 2007-035874 is known conventionally.

Such a substrate processing system includes a load lock chamber in which a cassette is stored, a processing chamber for processing a substrate to be processed, a transfer chamber installed in connection with the load lock chamber and the processing chamber, and a gas in the load lock chamber to exhaust the gas in the load lock chamber. A load lock chamber decompression means for depressurizing the gas, a purge gas supply means for supplying purge gas into the load lock chamber, a conveying chamber decompression means for evacuating the gas in the conveying chamber to depressurize the inside of the conveying chamber, and a gas in the processing chamber A processing chamber decompression means for depressurizing the inside of the processing chamber is provided.

The cassette accommodates a plurality of flat substrates, and the plurality of substrates are stored in a stacked shape at a predetermined interval in the vertical direction.

In addition, a conveying mechanism is provided in the conveying chamber, and a conveying mechanism is taken out by the conveying mechanism, and the substrate to be processed stored in the cassette in the load lock chamber is taken out and introduced into the processing chamber. It is taken out and stored in the cassette in the said load lock chamber.

Further, the purge gas supply means has a supply position for supplying purge gas into the load lock chamber at an upper position of the cassette, and the load lock chamber decompression means has an exhaust position for exhausting gas from the load lock chamber of the cassette. It is provided in the downward position, and the said cassette is arrange | positioned between the said supply position and the exhaust position.

As described above, according to the substrate processing system, first, the inside of the processing chamber is depressurized by the processing chamber depressurizing means, and the inside of the conveying chamber is depressurized by the conveying chamber depressurizing means, so that these processing chambers and the conveying chamber are in almost the same decompression state.

At the same time or after this, a cassette containing a plurality of substrates to be processed is stored in a load lock chamber under atmospheric pressure, and the load lock chamber is decompressed by the load lock chamber decompression means.

In this case, the purge gas is supplied into the load lock chamber by the purge gas supply means at the supply position provided above the cassette, while in the load lock chamber by the load lock chamber decompression means at the exhaust position installed below the cassette. The gas is exhausted. In this way, the load lock chamber is depressurized while the purge gas is supplied.

Thus, the cassette placed between the supply position and the exhaust position is exposed to a purge gas flow from the supply position toward the exhaust position.

When the inside of the load lock chamber is at the same pressure as the transfer chamber and the processing chamber, the substrate to be processed in the cassette is taken out by the transfer mechanism and introduced into the processing chamber. Then, a predetermined process is performed on the substrate to be processed in this processing chamber, and the substrate to be processed after processing is taken out by the transfer mechanism and stored in the cassette in the load lock chamber again.

Thereafter, when all the substrates to be processed in the cassette are processed in the same manner, the load lock chamber is brought to atmospheric pressure, and the cassette in which the processing is completed is replaced with an unprocessed cassette, and the processing is then performed in the same manner.

By the way, in the system which processes a board | substrate under reduced pressure (vacuum), organic substance generate | occur | produces from the movable part or friction part in a load lock chamber, and the phenomenon which organic substance flows back in the said load lock chamber pressure reduction means generate | occur | produces. Attachment to the substrate to be processed in the standby state in the load lock chamber causes a problem that the attached organic matter adversely affects the processing in the processing chamber.

Here, in the substrate processing system, by supplying a purge gas to the load lock chamber and exposing the cassette to such a purge gas flow, the organic material is prevented from entering the cassette by the purge gas flow and simultaneously It is actively discharged with the purge gas to the outdoors, and by these actions it is prevented that the organic matter adheres to the substrate to be processed.

Prior art literature

[Patent Document]

Patent Document 1: Japanese Unexamined Patent Publication No. 2007-035874

By the way, in the conventional substrate processing system, while the substrate to be processed is stored in the load lock chamber and in the standby state, purge gas is always supplied into the load lock chamber and gas is exhausted from the load lock chamber. There was further room for improvement in terms of reducing manufacturing costs, such as reducing the use of purge gas and reducing power consumption.

In particular, in view of reducing or preventing organic contamination, it is preferable to shorten the average free path of organic matter by supplying a large amount of purge gas into the load lock chamber and maintaining a high pressure in the load lock chamber. Likewise, if the amount of purge gas used is increased, there is a problem that the manufacturing cost is increased as described above.

Moreover, in the said conventional substrate processing system, there also existed a problem that the said organic substance contamination was easy to generate | occur | produce with respect to the topmost to-be-processed substrate accommodated in the cassette. In other words, in the conventional substrate processing system, as described above, the purge gas is supplied to the load lock chamber to expose the cassette to the purge gas flow, thereby preventing the organic matter from adhering to the substrate to be processed, but it is stored in the cassette. Many exposed parts from the cassette are exposed to the uppermost to-be-processed substrate. For this reason, such exposed parts can still be contacted with organic substances, and the exposed portions are likely to be contaminated by organic substances.

In particular, when the substrate to be processed is processed by a non-plasma process using a processing gas such as HF gas, the processing time is often longer than that of the plasma process, and the time for the substrate to be waited in the load lock chamber is increased. Because of this tendency to lengthen, the various problems described above become conspicuous.

In addition, in such a non-plasma process, the cleaning of the deposits (organic matters) on the physical surface of the substrate to be processed at the molecular level occurring in the plasma process is not performed. The contact with the processing gas is inhibited by this organic substance, causing problems such as lowering of the etching rate and deterioration of the etching uniformity. As a result, the yield of the good product of the substrate to be processed is lowered, resulting in higher processing cost. Generates.

The present invention has been made in view of the above circumstances, and in preventing organic contamination of a substrate to be processed, the manufacturing cost can be reduced, and organic contamination of the substrate to be processed in the load lock chamber can be more completely prevented. It is an object of the present invention to provide a substrate processing method and a substrate processing system.

The method according to the present invention for solving the above problems,

After storing the substrate to be processed in the load lock chamber, exhausting from the load lock chamber while supplying purge gas to the load lock chamber to depressurize the inside of the load lock chamber. A preparatory step of placing the exhaust position at a position above the processing substrate at a position below the processing substrate, and placing the processing substrate at the same time between the supply position and the exhaust position;

A transport mechanism in a transport chamber in a reduced pressure state connected to the load lock chamber, wherein the substrate to be processed in the load lock chamber is taken out and transported to a processing chamber in the same reduced pressure state while being connected to the transport chamber and installed therein. A substrate processing method comprising a processing step of processing a substrate to be processed in a processing chamber, and taking out a substrate to be processed after processing from the processing chamber by the transfer mechanism and storing it in the load lock chamber.

In the preparation step, the purge gas is supplied and exhausted, and when the pressure in the load lock chamber reaches the first reference pressure, the supply of the purge gas is stopped at the same time or later than the exhaust of the purge gas. It is related with the substrate processing method which restarts supply and exhaust of the said purge gas when the pressure in the said load lock chamber becomes the 2nd reference pressure higher than the said 1st reference pressure after stopping and stopping exhaust.

In addition, the apparatus of the present invention,

A load lock chamber in which a substrate to be processed is stored,

A processing chamber for processing the substrate to be processed,

A transfer chamber connected to the load lock chamber and the processing chamber;

A conveyance mechanism provided in the conveyance chamber, which takes out the object to be processed in the load lock chamber and introduces it into the process chamber, and takes out the object to be processed in the process chamber and stores it in the load lock chamber;

Load lock chamber decompression means for evacuating the gas in the load lock chamber to decompress the inside of the load lock chamber;

Purge gas supply means for supplying a purge gas into the load lock chamber;

Pressure detecting means for detecting a pressure in the load lock chamber;

Control means for controlling the operation of said load lock chamber decompression means and said purge gas supply means,

Conveying chamber decompression means for evacuating the gas in the conveying chamber to decompress the inside of the conveying chamber; and

A processing chamber decompression means for evacuating the gas in the processing chamber to decompress the inside of the processing chamber,

The purge gas supply means has a supply position for supplying the purge gas into the load lock chamber at an upper position of the substrate to be processed,

The load lock chamber decompression means is provided with an exhaust position for exhausting gas from the load lock chamber below the substrate to be processed,

A substrate processing system configured to place the substrate to be processed between the supply position and the exhaust position,

The control means,

While the substrate to be processed is stored in the load lock chamber, while the purge gas is supplied to the load lock chamber by the purge gas supply means, the load lock chamber is evacuated from the load lock chamber by means of the load lock chamber decompression means. When the pressure inside the load lock chamber detected by the pressure detecting means becomes the first reference pressure, the supply of the purge gas by the purge gas supply means stops at the same time or later than the pressure in the chamber. When the pressure in the load lock chamber detected by the pressure detecting means becomes a second reference pressure higher than the first reference pressure after the process of stopping the exhaust from the load lock chamber by the load lock chamber decompression means and the stop. And restarting the supply of purge gas by the purge gas supply means and the load lock chamber. A substrate processing system configured to execute a process for resuming exhaust from the load lock chamber by a decompression means.

According to the present invention, first, the interior of the processing chamber is depressurized by the processing chamber decompression means, and the interior of the conveyance chamber is depressurized by the conveying chamber decompression means, so that the processing chamber and the conveying chamber are in almost the same decompression state.

On the other hand, the substrate to be processed is stored in the load lock chamber under atmospheric pressure. The substrate to be processed is placed between the supply position and the exhaust position.

After the substrate to be processed is placed at a predetermined position, while the substrate to be processed is in the standby state in the load lock chamber, the following processing is performed under control by the control means.

That is, first, the gas in the load lock chamber is exhausted by the load lock chamber decompression means at an exhaust position provided at a lower position, and the rod is supplied by the purge gas supply means at a supply position provided at an upper position of the substrate to be processed. The purge gas is supplied into the lock chamber, and the load lock chamber is depressurized while the purge gas is supplied. In addition, nitrogen (N ₂ ) gas may be exemplified as the purge gas, but is not limited thereto.

In this manner, the substrate to be processed disposed between the supply position and the exhaust position is exposed to a purge gas flow from the supply position toward the exhaust position.

As described above, although organic matter may exist in the load lock chamber under reduced pressure, the organic substance is prevented from adhering to the substrate to be processed by exposing the substrate to be treated to the purge gas flow as in the prior art.

In the present invention, when the pressure in the load lock chamber detected by the pressure detecting means becomes the first reference pressure, the supply of the purge gas into the load lock chamber by the purge gas supply means stops at the same time or later. The exhaust from the load lock chamber by the lock chamber decompression means is stopped.

And after the stop, when the pressure in the load lock chamber detected by the pressure detecting means becomes a second reference pressure higher than the first reference pressure, the exhaust in the load lock chamber by the load lock chamber decompression means is While resuming, the supply of purge gas into the load lock chamber by the purge gas supply means is resumed, and the load lock chamber is further decompressed.

Thereafter, while the substrate to be processed is in the standby state in the load lock chamber, the supply and the exhaust of the purge gas are continuously stopped and the resumption is repeated.

The present inventors have earnestly studied to solve the above-described problems, and as a result, when the pressure in the load lock chamber is reduced to a predetermined pressure while supplying the purge gas into the load lock chamber, the inventors then supply the purge gas from the load lock chamber. Even if the exhaust of the gas was stopped, the action of preventing the adhesion of the organic substance to the substrate to be treated continued, so that the finding that the adhesion of the organic substance to the substrate to be treated was within the allowable range was attained.

According to the above-described conventional example, it has been recognized that the purge gas flow is indispensable in order to prevent the adhesion of organic matter to the substrate to be processed. However, as a result of intensive studies by the present inventors, the purge gas is supplied and exhausted from the load lock chamber. It was found that the action continued even when the reaction was stopped. It is considered that the action is maintained because the purge gas remains in the load lock chamber even when the supply of the purge gas and the exhaust from the load lock chamber are stopped, thereby suppressing the average free path of the organic matter.

In addition, since it is difficult to make the load lock chamber completely airtight, when the exhaust is stopped, outside air enters the load lock chamber by a leak, and the pressure in the load lock chamber is reduced. However, when taking out the substrate to be processed, it is necessary to return the pressure in the load lock chamber to the same pressure as the adjacent conveying chamber or the processing chamber. It is undesirable because it becomes necessary.

Here, in the present invention, when the pressure in the load lock chamber detected by the pressure detecting means becomes the second reference pressure higher than the first reference pressure, exhaust from the load lock chamber by the load lock chamber decompression means is resumed. In addition, the supply of the purge gas into the load lock chamber by the purge gas supply means was resumed.

In addition, according to the findings of the present inventors considering the above, the first reference pressure is preferably set within the range of about 10 Pa to about 30 Pa, and the second reference pressure is set within the range of about 15 Pa to about 300 Pa. It is preferable.

In addition, when the set pressure in the load lock chamber at the time of decompression is a considerably low pressure, exhausting while supplying purge gas may not reduce the pressure inside the load lock chamber up to this set pressure. In this case, when the supply and exhaust of the purge gas are stopped, the supply of the purge gas may be stopped first, and then the exhaust may be stopped later than a predetermined time later. By depressurizing in the state which stopped supply of purge gas, the pressure in a load lock chamber can be made into the said set pressure.

As described above, the substrate to be processed in the standby state in the load lock chamber is suitably taken out from the load lock chamber by the transfer mechanism and introduced into the processing chamber, so that a predetermined process is performed in the processing chamber. After that, it is returned to the load lock chamber by the conveying mechanism.

As described above, according to the present invention, since the substrate to be processed is exposed to the purge gas atmosphere while the substrate to be processed is in the standby state in the load lock chamber, it is possible to prevent organic substances from adhering to the substrate to be processed. .

Moreover, since the time which stops supply of purge gas and exhaust in a load lock chamber is provided in the range which can prevent the contamination of the organic substance of a to-be-processed board | substrate, it is possible to reduce the use of purge gas and to reduce the power consumption. Furthermore, it produces the effect that reduction of manufacturing cost can be aimed at.

In the present invention, the purge gas supply means includes a supply pipe whose one end is connected to a supply position of the load lock chamber, a purge open / close valve interposed in the supply pipe, and a purge gas supply part connected to the other end of the supply pipe. The load lock chamber pressure reducing means includes an exhaust pipe whose one end is connected to an exhaust position of the load lock chamber, an open / close valve for exhaust interposed in the exhaust pipe, and an exhaust pump connected to the other end of the exhaust pipe. Is composed by

The substrate processing system includes a pipe in which one end is connected to the supply pipe on the upstream side of the purge on / off valve and the other end is connected to the exhaust pipe on the downstream side of the exhaust on / off valve and a supply on / off valve interposed in such a pipe. Further provided,

The control means stops the supply of purge gas into the load lock chamber by closing the purge opening / closing valve in a state in which the purge gas supply is operated, and the opening and closing for exhaust in the state in which the exhaust pump is driven. Configured to shut off the exhaust from the load lock chamber by closing the valve,

After the exhaust from the load lock chamber is stopped, at the same time or later, the supply opening / closing valve is opened to supply the purge gas to the exhaust pipe through the pipe, and to flow downstream to the downstream of the exhaust pipe. And, at the same time or later than the execution of the resumption process, the supply closing valve is closed and the supply of the purge gas to the exhaust pipe is stopped.

While stopping the supply of the purge gas and at the same time stopping the exhaust from the load lock chamber, by supplying the purge gas to the exhaust pipe and circulating it downstream, it is possible to prevent the backflow of organic matter from the exhaust pump. In addition, since the organic matters can be prevented from infiltrating into the load lock chamber when the exhaust valve is opened and the exhaust gas is resumed, adhesion of the organic matters to the substrate to be processed can be prevented more effectively.

In addition, the supply amount (flow rate) of the purge gas supplied to the exhaust pipe during stop may be considerably smaller than the supply amount supplied to the load lock chamber, and in this sense, the use amount of the purge gas can be reduced as compared with the conventional one.

Incidentally, the timing for supplying the purge gas to the exhaust pipe does not have to be coincident with the stop of the exhaust from the load lock chamber, and may be supplied later than this. Similarly, the timing for stopping the supply of purge gas to the exhaust pipe does not have to be coincident with the execution of the resumption process, but may be stopped later than a predetermined time.

In the present invention, several substrates to be processed may be accommodated in a cassette at predetermined intervals in the vertical direction, and the accommodated cassette may be placed between the supply position and the exhaust position in the load lock chamber.

In this case, it is preferable that the cassette has a cover body which is disposed above the uppermost processing substrate among the stored processing substrates and covers at least the entire upper surface of the uppermost processing substrate.

As described above, in the aspect in which a plurality of substrates to be processed are stored in a cassette, there is a problem that the topmost substrate to be processed is more likely to be contaminated by organic substances than the substrate to be processed below, but the cover body is provided. Even with the uppermost to-be-processed substrate, contact with an organic substance is prevented by this cover body, and it can prevent that the organic substance adheres.

As described above, all the substrates stored in the cassette can be effectively prevented from being contaminated by organic matter.

In addition, the said cover body in this invention may be the same shape as a to-be-processed board | substrate, In this case, it can be accommodated in a cassette like a to-be-processed board | substrate, and the said cover body is located above the uppermost to-be-processed board | substrate. It is stored in a cassette.

Further, the cover member may constitute a top plate of a cassette. In this case, the said cover body is comprised so that the at least upper surface whole surface of the uppermost to-be-processed substrate accommodated may be covered.

According to the present invention, since the time for stopping the supply of the purge gas and the exhaust in the load lock chamber is provided within the range in which organic matter contamination of the substrate to be processed can be effectively prevented, the use of the purge gas can be reduced and the power consumption can be reduced. It can achieve, and also the effect that reduction of a manufacturing cost can be aimed at. Moreover, in the aspect which supplies a plurality of to-be-processed substrates stored in a cassette, contamination by organic matter can be prevented even with respect to the top-most to-be-processed substrate accommodated in a cassette, and with respect to all the to-be-processed substrates accommodated in a cassette They have the effect of being able to effectively prevent contamination by organic substances.

1 is a plan view showing a substrate processing system according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the arrow AA direction in FIG. 1. FIG.
3 is a cross-sectional view of the arrow BB direction in FIG. 1.
4 is a perspective view showing a cassette according to the present embodiment.
5 is a cross-sectional view showing a load lock chamber unit according to another embodiment of the present invention.
6 is a perspective view showing a cassette according to another embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of this invention is described based on drawing.

As shown in FIGS. 1-3, the substrate processing system 1 of this example is the conveyance chamber 40 in which the planar shape became square, the conveyance mechanism 45 arrange | positioned in this conveyance chamber 40, and the conveyance chamber ( 40 is a transfer chamber decompression mechanism 41 for depressurizing the inside, a load lock chamber 10 connected to one of the four outer circumferential surfaces of the transfer chamber 40 via a gate valve 11, and three other outer circumferential surfaces. Process chambers 50, 60, 70 connected to and installed through gate valves 51, 61, and 71, a load lock chamber decompression mechanism 25, and a load lock to depressurize the inside of the load lock chamber 10. The load lock chamber control unit 15 for controlling the operation of the purge gas supply mechanism 30, the load lock chamber decompression mechanism 25, the purge gas supply mechanism 30, and the like that supply the purge gas into the chamber 10, the above-described processing. Processing chamber decompression mechanisms 52, 62, 72, etc., which depressurize the chambers 50, 60, 70 respectively. The. Meanwhile, the transfer chamber 40, the transfer mechanism 45, the transfer chamber decompression mechanism 41, the gate valves 11, 51, 61, 71, the processing chambers 50, 60, 70, and the processing chamber decompression mechanism The operations 52, 62, 72 and the like are controlled by other control units (not shown).

As shown in FIG. 3, a mounting table 20 for mounting the cassette 80 is provided in the load lock chamber 10. The mounting table 20 is supported by the upper end of the elevating rod 22 installed in the vertical direction through the bottom surface of the load lock chamber 10, and the elevating driving unit connected to the lower end of the elevating rod 22. 21 moves up and down along the vertical direction. On the other hand, the penetrating portion penetrated by the elevating rod 22 of the load lock chamber 10 is properly sealed by a seal member, and the elevating rod 22 in the load lock chamber 10 has an upper end mounted thereon. It is fixed to the lower surface of 20, and the lower end is covered by the cylindrical corrugation box 23 fixed to the bottom surface in the load lock chamber 10. As shown in FIG.

In addition, an exhaust hole 12 is formed in the bottom surface of the load lock chamber 10. The load lock chamber pressure reducing mechanism 25 is connected to the exhaust hole 12, and the load lock chamber ( The air supply hole 13 is formed in the wall surface of 10, and the said purge gas supply mechanism 30 is connected to this air supply hole 13. As shown in FIG. The air supply hole 13 is disposed above the cassette 80 on the mounting table 20, and the cassette 80 is located in the middle connecting the air supply hole 13 and the exhaust hole 12.

As shown in FIG. 4, the cassette 80 has a structure in which a plurality of support grooves 81 supporting the substrate K are provided in the vertical direction at predetermined intervals. The substrate K is inserted into each of the supporting grooves 81 except for the same, and a cover 90 having the same shape as the substrate K is inserted into the uppermost support groove 81. Moreover, the to-be-processed substrate K and the cover body 90 are taken out from the opening side 82 of the cassette 80.

The load lock chamber decompression mechanism 25 has an exhaust pump 26, an exhaust pipe 27 having one end connected to the exhaust pump 26, and the other end connected to the exhaust hole 12, and an intermediate portion of the exhaust pipe 27. And the load lock chamber 10 through the exhaust hole 12 and the exhaust pipe 27 by the exhaust pump 26 when the exhaust opening / closing valve 28 is opened. ) Gas is exhausted and the pressure is reduced.

In addition, as shown, the purge gas supply mechanism 30 includes a purge gas supply unit 31, a supply pipe 32, a diffuser 33, a vent open / close valve 34, and a purge open / close valve 35. ) And the flow rate adjusting unit 36.

One end of the supply pipe 32 is connected to the purge gas supply part 31, and the other end thereof is connected to the air supply hole 13 of the load lock chamber 10, and an intermediate part thereof has two branch pipes ( Branched to 32a, 32b). The vent opening / closing valve 34 is provided in one branch pipe 32a, and the purging opening / closing valve 35 and the flow rate adjusting unit 36 are provided in the other branch pipe 32b.

In addition, the diffuser 33 is a cup-shaped member fixed to the inner wall surface to cover the air supply hole 13 that is opened on the inner wall surface of the load lock chamber 10, and a plurality of through holes are drilled in the plane. It is.

In this way, according to the purge gas supply mechanism 30, purge gas is supplied from the purge gas supply unit 31 to the supply pipe 32, the load lock through the through holes of the air supply hole 13 and the diffuser 33 Purge gas flows into the chamber 10.

At this time, when the vent open / close valve 34 is opened and the purge open / close valve 35 is closed, a large amount of purge gas is supplied into the load lock chamber 10 through the vent open / close valve 34, and The load lock chamber 10 is at atmospheric pressure. In addition, after the inside of the load lock chamber 10 reaches atmospheric pressure, the opening / closing valve 34 for the vent is closed.

On the other hand, when the vent opening / closing valve 34 is closed and the purging opening / closing valve 35 is open, the purge gas having the flow rate adjusted by the flow rate adjusting unit 36 is loaded through such a purging opening / closing valve 35. Supplied into chamber 10.

The transfer chamber decompression mechanism 41 includes an exhaust pump 42, one end of which is connected to the exhaust pump 42, and the other end of the exhaust pipe 43 and the exhaust pipe 43 connected to the transfer chamber 40. And a gas in the conveyance chamber 40 by the exhaust pump 42 through the exhaust pipe 43 when the on / off valve 44 is in an open state. Decompression

The conveyance mechanism 45 is supported by the support base 46, the support base 46 so that the axis is in the vertical direction, and the support shaft 47 which slides up and down in the vertical direction, and the support shaft ( And a pick-up hand 49 provided at the distal end of the arm 48 and horizontally supported in the horizontal plane.

The processing chamber decompression mechanisms 52, 62, 72 are respectively connected to exhaust pumps 53, 63, 73, one end of which is connected to these exhaust pumps 53, 63, 73, and the other end of each of the processing chambers ( Exhaust pipes 54, 64, 74 connected to 50, 60, 70, on-off valves 55, 65, 75, etc. installed in the middle of the respective exhaust pipes (54, 64, 74), etc. Gas in each of the processing chambers 50, 60, 70 through the exhaust pipes 54, 64, 74 by the exhaust pumps 53, 63, 73 when the valves 55, 65, 75 are open. Is exhausted and the pressure is reduced to a predetermined pressure.

In addition, the processing chambers 50, 60, and 70 are processing chambers for processing the substrate K, and a detailed structure thereof is omitted. For example, hydrogen fluoride (HF) gas, alcohol Various processes such as etching the silicon oxide (SiO ₂ ) film on the substrate K are performed by a mixed gas of steam (ethanol, methanol, etc.) and nitrogen (N ₂ ) gas.

The load lock chamber control unit 15 is a purge gas supply unit 31 of the purge gas supply mechanism 30, a vent open / close valve 34, a purge open / close valve 35, a flow rate control unit 36, and the rod It is comprised so that operation | movement of the exhaust pump 26 and the exhaust opening-closing valve 28 of the lock chamber pressure reduction mechanism 25, and the said lift drive part 21 may be controlled.

In addition, the load lock chamber 10 is provided with a pressure detector 17 for detecting the pressure therein, the detection signal according to the pressure detected by the pressure detector 17 is the load lock chamber control unit ( 15).

According to the substrate processing system 1 of the present example having the above-described configuration, first, under the control by the other control unit (not shown) described above, the respective processing chambers (by the processing chamber decompression mechanisms 52, 62, 72) ( 50, 60, 70, while the pressure is reduced, the inside of the conveyance chamber 40 by the conveyance chamber decompression mechanism 41 is decompressed, and in the process chambers 50, 60, 70 and in the conveyance chamber 40 are almost the same. It will be in a reduced pressure (vacuum) state. In addition, in the following operation | movement description, the conveyance chamber 40, the conveyance mechanism 45, the conveyance chamber decompression mechanism 41, the gate valves 11, 51, 61, 71, the processing chambers 50, 60, 70), the operation of the processing chamber decompression mechanisms 52, 62, 72 and the like is executed under control by the corresponding control unit (not shown).

Meanwhile, the cassette 80 in which the plurality of substrates K are stored is stored in the load lock chamber 10 under atmospheric pressure.

In the cassette 80, as shown in FIG. 4, the several to-be-processed substrate K is accommodated, Furthermore, the cover body 90 of the same shape is accommodated above the uppermost to-be-processed substrate K. The entire upper surface of the uppermost target substrate K is covered by the cover 90. The cassette 80 is placed on the mounting table 20 in the load lock chamber 10 so that the opening side 82 is opposed to the transfer chamber 40.

When the cassette 80 is placed on the mounting table 20, the following operations are executed under the control of the load lock chamber controller 15. In addition, in the following operation | movement description, the purge gas supply part 31, the vent open / close valve 34, the purge open / close valve 35, the flow volume adjusting part 36, the exhaust pump 26, and the exhaust open / close valve 28 And the operation of the lift driver 21 are executed under the control of the load lock chamber controller 15.

That is, first, the exhaust pump 26 of the load lock chamber decompression mechanism 25 is driven and the exhaust opening / closing valve 28 is opened, whereby the gas in the load lock chamber 10 is exhausted. On the other hand, the purge gas supply mechanism 30 is driven while the purge gas supply unit 30 is driven, and the vent open / close valve 34 is in a closed state, and the purge open / close valve 35 is in an open state. The purge gas of the flow volume adjusted by the adjustment part 36 is supplied into the load lock chamber 10 via the purge opening / closing valve 35. As described above, the load lock chamber 10 is depressurized while the purge gas is supplied. On the other hand, as a purge gas, but it not intended to be mentioned nitrogen (N ₂₎ gas, like.

As such, the cassette 80 mounted on the mounting table 20 is discharged from the through hole of the diffuser 33 to be exposed to the purge gas flow toward the exhaust hole 12.

Then, when the load lock chamber 10 is about the same pressure as the transfer chamber 40 and the processing chambers 50, 60, 70, the processing mechanism 45 in the cassette 80 is carried out by the transfer mechanism 45. The substrate K is taken out.

That is, the conveyance mechanism 45 first rotates the support shaft 47 about the shaft to replace the pick-up hand 49 with the load lock chamber 10. Then, the gate valve 11 is opened, and the conveying mechanism 45 extends the arm 48 to bring the pick-up hand 49 into the load lock chamber 10 through the gate valve 11. Enter

At this time, the position of the mounting table 20 is adjusted by the elevating mechanism part 21 so that the position of the pick-up hand 49 is located slightly below the processing target substrate K to be taken out. And the pick-up hand 49 is inserted below the target substrate K. As shown in FIG.

Subsequently, the conveyance mechanism 45 raises the support shaft 47 slightly, receives the said to-be-processed board | substrate K on the pick-up hand 49, and shrinks the arm 48 after that. ) Is taken out of the cassette 80 and taken out from the load lock chamber 10. After that, the gate valve 11 is closed.

Next, the conveyance mechanism 45 introduces the to-be-processed substrate K taken out in this manner into a predetermined, for example, processing chamber 50. Although a detailed description of the introduction operation is omitted, the predetermined processing is then performed on the substrate in the processing chamber 50.

In addition, the same processing may be performed in each of the processing chambers 50, 60, and 70, and different processing may be performed in each of the processing chambers. A series of treatments may be performed on the substrate K to be processed by passing through it.

And when the predetermined process is finished with respect to the to-be-processed board | substrate K, the said conveyance mechanism 45 takes out the to-be-processed board | substrate K from the process chambers 50, 60, and 70, and the cassette in the load lock chamber 10 is carried out. It is stored in (80) again.

In this manner, when the processing is completed for all the substrates K stored in the cassette 80, the purge gas supply mechanism 30 closes the purge open / close valve 35 and closes the vent open / close valve 34. It opens and supplies a large amount of purge gas into the load lock chamber 10, and makes the inside of the load lock chamber 10 into atmospheric pressure. On the other hand, at this time, the load lock chamber pressure reducing mechanism 25 closes the exhaust opening / closing valve 28. The timing of closing the exhaust opening / closing valve 28 may be simultaneous with the opening operation of the vent opening / closing valve 34 or may be before such opening operation.

After the inside of the load lock chamber 10 has become atmospheric pressure, the completed cassette 80 and the unprocessed cassette 80 are exchanged, and the same process is performed thereafter.

In the above processing step, the load lock chamber control unit 15 performs the following operations while the cassette 80 is in the standby state in the load lock chamber 10.

That is, the load lock chamber control unit 15 monitors the pressure in the load lock chamber 10 detected by the pressure detector 17, and when the pressure reaches the predetermined first reference pressure, the purge open / close valve 35 ), The supply of the purge gas to the load lock chamber 10 is stopped, and at the same time or later, the exhaust opening / closing valve 28 is closed and the exhaust from the load lock chamber 10 is stopped. On the other hand, the exhaust pump 26 and the purge gas supply part 31 may stop these operations at this time, and may continue the state driven continuously.

After stopping the supply and exhaust of the purge gas in this way, when the pressure in the load lock chamber detected by the pressure detecting means becomes the second reference pressure higher than the first reference pressure, the load lock chamber control unit 15 performs the above-mentioned. Opening and closing the exhaust valve 28 (the exhaust pump 26 is also driven when the exhaust pump 26 is stopped) to open and close the purge at the same time while resuming the exhaust from the load lock chamber 10. The valve 35 is opened (if the operation of the purge gas supply part 31 is stopped, it is operated) to resume the supply of the purge gas to the load lock chamber 10.

After that, the supply and exhaust of the purge gas and the stopping and resumption of the purge gas are repeatedly executed based on the first reference pressure and the second reference pressure.

As mentioned above, although the specific structure and operation | movement of the substrate processing system 1 which concerns on this embodiment were demonstrated above, As can be seen from the said description, according to the substrate processing system 1 which concerns on this embodiment, the load lock chamber Since the purge gas is supplied to the load lock chamber 10 by the purge gas supply mechanism 30 while the substrate K to be waited in the atmosphere 10 is to be treated by such a purge gas flow. The housed cassette 80 of the substrate K is exposed, and intrusion of organic matter into the cassette is prevented by such a purge gas flow. In addition, the organic material is discharged out of the load lock chamber 10 together with the purge gas, and by this action, the organic material is prevented from adhering to the substrate K to be processed.

In the substrate processing system 1 according to the present embodiment, when the pressure in the load lock chamber 10 becomes the first reference pressure, the exhaust gas from the load lock chamber 10 and the load lock chamber 10 are affected. The supply of the purge gas into the c) is stopped and the exhaust and the supply are resumed when the pressure in the load lock chamber 10 becomes the second reference pressure, which is the purge gas in the load lock chamber 10. When the inside of the load lock chamber 10 is depressurized to a predetermined pressure while supplying P, the action of preventing the adhesion of organic matter to the substrate K is maintained even after the supply and exhaust of the purge gas are stopped. It is based on the knowledge of the present inventors that adhesion of the organic substance to the processing substrate K exists within an acceptable range.

According to the conventional example described above, in order to prevent adhesion of organic matter to the processing target substrate K, it has been recognized that the purge gas flow is indispensable. It has been found that the above action continues even when the exhaust from the inside of the cylinder is stopped. Here, the action is continued, even if the supply of purge gas and the exhaust from the load lock chamber 10 are stopped, the purge gas remains in the load lock chamber 10, whereby the average free path of organic matter is suppressed. I think it is because.

In addition, since it is difficult to make the load lock chamber 10 completely airtight, when the exhaust is stopped, outside air enters the load lock chamber 10 by a leak, and the load lock chamber ( 10, but the pressure in the load lock chamber 10 is returned to the same pressure as the adjacent transfer chamber 40 or the processing chambers 50, 60, 70 when taking out the substrate K to be processed. Since it is necessary, if the pressure in the load lock chamber 10 is too high, it is not preferable because it requires time to decompress it.

Therefore, in the present example, when the pressure in the load lock chamber 10 detected by the pressure detector 17 becomes the second reference pressure higher than the first reference pressure, the exhaust and purge gas are resumed.

Moreover, according to the knowledge of the present inventors, it is preferable to set the said 1st reference pressure in the range of about 10 Pa to about 30 Pa. In addition, the second reference pressure is preferably set in the range of about 15 Pa to about 300 Pa.

Experimental Example 1

In addition, the first reference pressure is set to 10 Pa, the second reference pressure is set to 15 Pa, and the uppermost target substrate K in the cassette 80 is not covered with the cover 90. The cassette 80 is stored in the load lock chamber 10 and the silicon oxide (SiO ₂ ) on the substrate K is processed by a mixed gas of hydrogen fluoride (HF) gas, ethanol vapor and nitrogen (N ₂ ) gas. The process of etching the film is performed, and the first substrate K (the lowest substrate K in the cassette 80) and the substrate K waited for three hours in the load lock chamber 10 ( The etching rate and uniformity of etching of the uppermost substrate K in the cassette 80 were compared, and both were equivalent.

In the present embodiment, the upper surface of the upper surface of the processing target substrate K located in the uppermost portion of the processing target substrate K accommodated in the cassette 80 is covered by the cover 90 disposed above. Since it is covered, contact with organic substance is prevented by such a cover body 90, and it can prevent that an organic substance adheres similarly to the uppermost to-be-processed substrate K similarly.

A treatment such as etching a silicon oxide (SiO ₂ ) film on a substrate K by a mixed gas of hydrogen fluoride (HF) gas, alcohol (ethanol, methanol, etc.) vapor and nitrogen (N ₂ ) gas described above. In this case, although the processing time is long and there is a high risk that the substrate K is to be contaminated by the organic substance, according to the substrate processing system 1 according to the present embodiment, even in such a case, the organic substance is treated on the substrate K. This adhesion can be prevented efficiently.

Experimental Example 2

In addition, as described above, the first reference pressure is set to 10 Pa, the second reference pressure is set to 15 Pa, and the uppermost target substrate K in the cassette 80 is covered with the cover 90. The silicon oxide (SiO ₂ ) film on the substrate K is etched in the load lock chamber 10 by a mixed gas of hydrogen fluoride (HF) gas, ethanol vapor, and salo (N ₂ ) gas. The processing was carried out, and the first to-be-processed substrate K (lowest to-be-processed substrate K in the cassette 80) and the to-be-processed substrate K (cassette 80) were placed in the load lock chamber 10 for 14 hours. The etching rate and the uniformity of etching of the uppermost to-be-processed substrate K in () were compared, and both were equivalent.

Experimental Example 3

On the other hand, without protecting the uppermost to-be-processed substrate K with the cover 90, the same process as in Experimental Example 2 was performed to wait 14 hours in the first to-be-processed substrate K and the load lock chamber 10. When comparing the etching rate and the uniformity of etching with the topmost substrate K, the etching rate of the topmost substrate K is about 10% slower than that of the first substrate K, Etch uniformity was degraded by 50%.

As described above, according to the substrate processing system 1 according to the present embodiment, it is possible to efficiently protect this from the contamination of organic matter even for the uppermost target substrate K accommodated in the cassette 80. With respect to all the substrates K contained in the substrate 80, they can be prevented from being contaminated by organic matters efficiently.

In addition, when the set pressure in the load lock chamber 10 at the time of decompression is a considerably low pressure, evacuating while supplying purge gas may not reduce the inside of the load lock chamber 10 to this set pressure. . In this case, when the supply and exhaust of the purge gas are stopped, the supply of the purge gas may be stopped first, and then the exhaust may be stopped later than a predetermined time later. By depressurizing in the state which stopped supply of purge gas, the pressure in the load lock chamber 10 can be made into the said set pressure.

As described above, the time for stopping the supply and exhaust of the purge gas is provided in a range in which organic contamination of the substrate K can be effectively prevented, so that the amount of purge gas used and the power consumption can be reduced. Furthermore, it has the effect that reduction of manufacturing cost can be aimed at.

As mentioned above, although specific embodiment of this invention was described, the aspect which this invention can employ | adopt is not limited to this at all.

For example, as shown in FIG. 5, in the substrate processing system 1 described above, one end is connected to the supply pipe 32b on the upstream side of the purge on / off valve 35 and the exhaust on / off valve ( A pipe 38 having the other end connected to the exhaust pipe 27 on the downstream side may be provided, and the opening and closing valve 39 for supply may be interposed in the pipe 38.

In this case, when the pressure in the load lock chamber 10 reaches the first reference pressure, the load lock chamber control unit 15 operates the purge gas supply unit 31 in the state where the purge open / close valve 35 is operated. Stops the supply of purge gas into the load lock chamber 10 by closing the valve, and closes the exhaust opening / closing valve 28 in the state where the exhaust pump 26 is driven. (10) The exhaust gas from the inside is stopped, and the purge gas is supplied to the exhaust pipe 27 through the pipe 38 by opening the supply opening / closing valve 39 at the same time as or later than the stop of the exhaust, while the load lock When the pressure in the chamber 10 reaches the second reference pressure, the supply of purge gas into the load lock chamber 10 and the evacuation from the load lock chamber 10 are resumed at the same time or later. Opening and closing bell for the supply Close 39 is configured to stop the supply of purge gas to the exhaust pipe (27).

In the substrate processing system 1 configured in this manner, while the supply of the purge gas into the load lock chamber 10 is stopped, while the exhaust gas from the load lock chamber 10 is stopped, the pipe 38 The purge gas is supplied to the exhaust pipe 27 through circulating and flows toward the downstream side thereof.

By doing so, it is possible to prevent backflow of organic matter from the exhaust pump 26 and to prevent organic matter from entering the load lock chamber 19 when opening the exhaust opening / closing valve 28 to resume the exhaust. As a result, adhesion of organic substances to the substrate K can be prevented more effectively.

In addition, the supply amount (flow rate) of the purge gas supplied to the exhaust pipe during the stop may be much smaller than the supply amount supplied to the load lock chamber 10, and in this sense, the amount of purge gas used can be reduced as compared with the conventional one.

The cover 90 has the same shape as that of the substrate K, but is not limited thereto, and can be housed in the cassette 80 in the same manner as the substrate K, and at least to be covered. Any shape may be sufficient as long as the whole upper surface of the processing board K can be covered.

In addition, the cover body 90 does not need to be different from the cassette 80, and as shown in FIG. 6, the top plate 85 of the cassette 80 may be comprised as a cover body. In this case, the top plate 85 is comprised so that the at least upper surface whole surface of the uppermost to-be-processed substrate K accommodated may be covered.

1: substrate processing system 10: load lock chamber
12: exhaust ball 13: air supply
15: load lock chamber control part 17: pressure detector
25: load lock chamber decompression mechanism 26: exhaust pump
27: exhaust pipe 28: exhaust valve
30: purge gas supply mechanism 31: purge gas supply part
32: supply pipe 33: diffuser
34: Vent opening / closing valve 35: Purge opening / closing valve
38: piping 39: supply closing valve
40: conveying chamber 41: conveying chamber decompression mechanism
45: conveyance mechanism 50, 60, 70: processing chamber
52, 62, 72: Processing chamber decompression mechanism 80: Cassette
90: cover body K: substrate to be processed

Claims (12)

Storing the substrate to be processed in the load lock chamber, exhausting the load into the load lock chamber while supplying a purge gas to the load lock chamber, and depressurizing the inside of the load lock chamber. A preliminary step of placing an exhaust position at an upper position of the processing substrate at a lower position of the substrate to be processed and placing the substrate to be processed between the supply position and the exhaust position; And
Take out the to-be-processed substrate in the load lock chamber by the conveyance mechanism in the conveyance chamber which is connected to the load lock chamber, and convey it to the same process chamber in the reduced pressure state which is connected to the conveyance chamber and installed. And a processing step of processing the substrate to be processed in the processing chamber, and taking out the substrate to be processed from the processing chamber by the transfer mechanism and storing it in the load lock chamber.
In the preparation step, the purge gas is supplied and exhausted to stop the supply of the purge gas when the pressure in the load lock chamber reaches the first reference pressure, and at the same time or later, the exhaust gas in the load lock chamber is stopped. And supplying and exhausting the purge gas when the pressure in the load lock chamber becomes a second reference pressure higher than the first reference pressure after stopping the exhaust. The substrate processing method according to claim 1, wherein in the preparation step, the purge gas is supplied to an exhaust pipe connected to an exhaust position of the load lock chamber, and the purge gas is circulated toward a downstream side in the exhaust pipe. ,
At the same time as or later than after the exhaust is stopped, the supply of purge gas to the exhaust pipe is started, and the supply of the purge gas to the exhaust pipe is stopped at the same time or later after the supply of the purge gas and the exhaust is resumed. Substrate processing method characterized in that. The substrate processing method according to claim 1 or 2, wherein the first reference pressure is set within a range of 10 Pa to 30 Pa, and the second reference pressure is set within a range of 15 Pa to 300 Pa. The method according to claim 1 or 2, wherein the plurality of substrates to be processed are placed between the supply position and the exhaust position in the load lock chamber in a state of being accommodated in a cassette at a predetermined interval in the vertical direction, A substrate processing method characterized by covering at least an upper surface of the uppermost target substrate among the target substrates stored in the cassette with a cover body provided above. The method of claim 4, wherein
The cover body having the same shape as that of the substrate to be processed is used, and the cover body is stored in the cassette so as to be positioned above the substrate to be processed at the uppermost level to cover the entire upper surface of the substrate to be processed at the uppermost level. Substrate processing method. 5. The substrate processing method according to claim 4, wherein a top plate is provided in the cassette, and the top plate covers at least an entire upper surface of the uppermost target substrate. A load lock chamber in which a substrate to be processed is stored;
A processing chamber for processing the substrate to be processed;
A transfer chamber connected to the load lock chamber and the processing chamber;
A conveying mechanism provided in the conveying chamber, taking out a substrate to be processed in the load lock chamber and introducing the substrate into the processing chamber, and taking out the substrate to be processed in the processing chamber and storing it in the load lock chamber;
Load lock chamber decompression means for evacuating a gas in the load lock chamber to decompress the inside of the load lock chamber;
Purge gas supply means for supplying a purge gas into the load lock chamber;
Pressure detecting means for detecting a pressure in the load lock chamber;
Control means for controlling the operation of said load lock chamber decompression means and said purge gas supply means;
Conveying chamber decompression means for evacuating the gas in the conveying chamber to decompress the inside of the conveying chamber; And
A processing chamber decompression means for evacuating the gas in the processing chamber to decompress the inside of the processing chamber,
The purge gas supply means has a supply position for supplying the purge gas into the load lock chamber at an upper position of the substrate to be processed,
The load lock chamber decompression means is provided with an exhaust position for exhausting gas from the load lock chamber below the substrate to be processed,
A substrate processing system in which the substrate to be processed is configured to be placed between the supply position and the exhaust position,
Wherein,
While the substrate to be processed is stored in the load lock chamber,
While the purge gas is supplied by the purge gas supply means into the load lock chamber, the load lock chamber is evacuated by the load lock chamber decompression means to lower the pressure in the load lock chamber, and by the pressure detecting means. When the pressure in the load lock chamber to be detected reaches a first reference pressure, the load lock chamber decompression means by the load lock chamber decompression means stops the supply of the purge gas by the purge gas supply means or later. A process of stopping the exhaust from the gas; And
After the stop, when the pressure in the load lock chamber detected by the pressure detecting means becomes a second reference pressure higher than the first reference pressure, supply of the purge gas by the purge gas supply means is resumed. And processing for resuming exhausting in the load lock chamber by the load lock chamber decompression means. 8. The purge gas supply means according to claim 7, wherein the purge gas supply means has a supply pipe connected to a supply position of the load lock chamber, a purge open / close valve interposed in the supply pipe, and a purge gas supply connected to the other end of the supply pipe. ,
The load lock chamber decompression means includes an exhaust pipe whose one end is connected to an exhaust position of the load lock chamber, an exhaust opening / closing valve interposed in the exhaust pipe and an exhaust pump connected to the other end of the exhaust pipe,
The substrate processing system has a supply opening / closing valve interposed between a pipe having one end connected to the supply pipe on the upstream side of the purge on / off valve and connected to the pipe having the other end connected to the exhaust pipe downstream from the exhaust opening / closing valve. Further provided,
The control means stops the supply of purge gas into the load lock chamber by closing the purge on / off valve in the state in which the purge gas supply is operated, and simultaneously opens and closes the exhaust in the state in which the exhaust pump is driven. Closing the valve to stop exhaust from within the load lock chamber,
Stopping the exhaust from the load lock chamber and simultaneously opening or closing the supply opening / closing valve, supplying the purge gas to the exhaust pipe through the pipe, and distributing it downstream in the exhaust pipe; And at the same time or later than after the execution of the resuming process, to close the supply opening and closing valve and stop the supply of the purge gas to the exhaust pipe. The substrate processing system according to claim 7 or 8, wherein the first reference pressure is set within a range of 10 Pa to 30 Pa, and the second reference pressure is set within a range of 15 Pa to 300 Pa. The method of claim 7 or 8, further comprising a cassette for receiving a plurality of substrates to be processed at a predetermined interval in the vertical direction,
The cassette is placed between the supply position and the exhaust position in the load lock chamber,
And the cassette further comprises a cover body disposed above the uppermost target substrate among the stored target substrates and covering at least an upper surface of the uppermost target substrate. The substrate processing system according to claim 10, wherein the cover has the same shape as the substrate to be processed. The substrate processing system according to claim 10, wherein the cover body constitutes a top plate of the cassette, and the top plate covers at least the entire upper surface of the substrate to be processed at the uppermost level.

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