JP2010141000A - Substrate processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To process even one fractional wafer which is left unprocessed in the same manner with normal processing even in such a case. <P>SOLUTION: A two-sheet semiconductor manufacturing device executes a fraction stack conveyance flow when one fractional wafer 1 is left. An external transfer device 30 picks up a wafer 1 at a final-stage mounting part 28 of a support base 20 of a first load lock chamber 14a with a lower finger 32b. Then the external transfer device 30 moves a finger assy 32 holding the wafer 1 with the lower finger 32b to a second load lock chamber 14b and picks up a wafer 1 at a first-stage mounting part 28 of the support base 20 of the second load lock chamber 14b with an upper finger 32a. Then the external transfer device 30 moves the finger assy 32 to a first processing chamber 16a while holding the wafers 1 and 1 with the upper finger 32a and lower finger 32b, and stops above a first processing section 36. The first processing section 36 performs the normal two-sheet processing. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a substrate processing apparatus.

  For example, as a substrate processing apparatus for forming an insulating film, a metal film, and a semiconductor film on a semiconductor wafer (hereinafter referred to as a wafer) on which a semiconductor integrated circuit device (hereinafter referred to as an IC) is formed, two wafers are carried into a processing chamber. Thus, there is a two-wafer semiconductor manufacturing apparatus that forms a film simultaneously. For example, see Patent Document 1.

JP 2001-7030 A

In general, 25 wafers to be handled in an IC manufacturing method are accommodated in a carrier by 25 sheets and transported in and between processes.
In a two-wafer semiconductor manufacturing apparatus, 25 wafers carried by a carrier are carried into a processing chamber in units of two and processed according to a designated process recipe.
Process recipes are individually assigned to each wafer to be processed.
At the start of lot processing, the number of wafers that can be selected in one process recipe (this processing unit is called a process job) varies from a minimum of 1 to a maximum of 25 (corresponding to the number of slots in the carrier). It cannot be selected for a carrier.
Therefore, in order to process two carriers, it is necessary to select two or more process jobs. At this time, it is possible to select the same recipe, but in this case, even if the process recipe is the same, the process jobs are different.
When two wafers are loaded into the processing chamber, the last one is a fraction in a process job in which an odd number of wafers is selected. The following two control methods can be selected for this last wafer.
(1) Dummy wafer control method A dummy wafer prepared in advance is added to the last one and two, and then loaded into the processing chamber.
Advantage: Processing can be performed under the same conditions as other wafers, so uniformity can be maintained.
Disadvantages: Complicated management, such as securing dedicated slots for dummy wafers and limiting the number of uses. (2) Non-control method Process with one sheet as it is.
Advantage: Management is simple.
Disadvantages: It is not possible to guarantee the identity of one processed wafer with two simultaneous processed wafers.

  An object of the present invention is to provide a substrate processing apparatus that can perform processing in the same manner as in normal processing even when fractions are generated.

Typical means for solving the above-described problems are as follows.
(1) a plurality of processing chambers for processing a substrate;
A first transfer chamber provided with a first transfer means for transferring a substrate to each processing chamber;
A second transfer chamber provided with a second transfer means for transferring a substrate in an atmospheric pressure state;
A depressurizable spare chamber connecting the first transfer chamber and the second transfer chamber;
In the substrate processing apparatus provided with the control means for controlling the transfer of the first transfer means and the second transfer means between the substrate storage means storing a plurality of substrates and the processing chamber,
In the case where processing is continuously performed across a plurality of the substrate storage means according to the operation recipe assigned to the substrate placed in the slot provided in the substrate storage means, the first substrate storage means A substrate processing apparatus for simultaneously processing a last substrate placed and a first substrate placed in the second substrate storage means.
(2) When the substrate is processed continuously over a plurality of the substrate storage means according to the operation recipe assigned to the substrate placed in the slot provided in the substrate storage means, the first substrate storage A substrate processing method comprising: simultaneously processing a last substrate placed on the means and a first substrate placed on the second substrate storage means.

  According to the above-described means, even when a fraction occurs, processing can be performed in the same manner as in normal processing.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  In the present embodiment, the substrate processing apparatus according to the present invention is configured as a two-wafer semiconductor manufacturing apparatus 10.

  As shown in FIG. 1, the two-wafer semiconductor manufacturing apparatus 10 has two load lock chambers 14 a and 14 b and two processing chambers 16 a and 16 b arranged around a transfer chamber 12. An EFEM (Equipment Front End Module) 18 that is a front module is disposed upstream of the two load lock chambers 14a and 14b.

Although not shown, the EFEM 18 has a structure capable of mounting three carriers. The carrier has 25 stages of slots, and each stage slot is configured to hold one wafer at a time. Therefore, the carrier can accommodate a minimum of 1 to a maximum of 25 wafers.
Although not shown, a wafer transfer equipment is installed in the EFEM 18, and the wafer transfer equipment can transfer a plurality (usually, five) of wafers simultaneously in the atmosphere. The wafer transfer device enables wafer transfer between the two load lock chambers 14a and 14b.

As shown in FIG. 2, the load lock chambers 14a and 14b are provided with a support base 20, and the support base 20 accommodates 25 wafers at regular intervals in the vertical direction. The support base 20 is made of, for example, silicon carbide or aluminum, and has, for example, three support columns 26 that connect the upper plate 22 and the lower plate 24. For example, 25 placement portions 28 are formed in parallel in the longitudinal direction of the column 26.
In addition, the support base 20 is configured to move in the vertical direction (move up and down) in the load lock chambers 14a and 14b, and to rotate about a rotation axis extending in the vertical direction. ing.

A wafer transfer device 30 is installed in the transfer chamber 12. The wafer transfer device 30 transfers the wafer 1 between the load lock chambers 14a and 14b and the processing chambers 16a and 16b. The wafer transfer device 30 includes an arm 34 provided with a finger assembly 32. The finger assembly 32 has an upper finger 32a and a lower finger 32b. The upper finger 32a and the lower finger 32b have the same shape, are spaced apart at a predetermined interval in the vertical direction, and extend substantially horizontally from the arm 34 in the same direction to support the wafer 1 respectively. The arm 34 is configured to rotate about a rotation axis extending in the vertical direction and to move in the horizontal direction.
The transfer chamber 12 and the processing chamber 16a communicate with each other via the gate valve 35 (see FIG. 3).

  Therefore, the wafer transfer device 30 installed in the transfer chamber 12 transfers unprocessed wafers stocked in the load lock chambers 14a and 14b to the process chambers 16a and 16b through the gate valve 35 two by two at the same time. In addition, two processed wafers can be transferred from the processing chambers 16a and 16b to the load lock chambers 14a and 14b two at a time.

As shown in FIG. 3, two holding bases 37 and 37 are placed in the processing chamber 16. The holding table 37 on the transfer chamber 12 side is referred to as a first processing unit 36, and the other holding table 37 is referred to as a second processing unit 38. The first processing unit 36 and the second processing unit 38 have independent structures, and are viewed in the same direction as the wafer processing flow direction when viewed from the whole apparatus. That is, the second processing unit 38 is disposed far from the transfer chamber 12 with the first processing unit 36 interposed therebetween.
The first processing unit 36 and the second processing unit 38 communicate with each other, and the temperature inside the processing chamber 16 can be increased to 300 ° C. The 1st process part 36 and the 2nd process part 38 are formed, for example with aluminum, and are heated by the heater (not shown) inserted.
In order to achieve the purpose of space saving and cost reduction, the load lock chambers 14a and 14b, the transfer chamber 12 and the processing chambers 16a and 16b may be formed of, for example, a single piece of aluminum.

  Near the inside of the processing chamber 16 between the first processing section 36 and the second processing section 38, a processing chamber wafer transfer device (hereinafter referred to as an inner transfer device) 40 is provided. The inner transfer device 40 transfers one of the two unprocessed wafers conveyed by the wafer transfer device (hereinafter referred to as the outer transfer device) 30 to the second processing unit 38, and further The processed wafer of the processing unit 38 is transferred onto the finger assembly 32 of the outer transfer device 30.

FIG. 4 shows a state when the inner transfer device 40 in the processing unit 16 stands by on the second processing unit 38 side (during wafer processing).
The inner transfer device 40 includes a circular arc portion 43a larger than the outer diameter of the wafer, a cutout portion 43b cut out from the circular arc portion 43a, and a wafer provided substantially horizontally from the circular arc portion 43a to the center of the circular arc portion. It has a claw portion 43c to be placed and an arm 47 provided with a frame portion 43d that supports the arc portion 43a.
The arc portion 43a and the frame portion 43d are formed continuously, are mounted substantially horizontally from the arm 47, and support the wafer 1 via the claw portion 43c.
The arm 47 is configured to rotate about a shaft portion 43e extending in the vertical direction as a rotation axis and to move up and down in the vertical direction.
The notch 43 b is disposed at a position facing the gate valve 35 provided between the transfer chamber 12 and the processing chamber 16 when the shaft 43 e rotates and is positioned on the first processing portion 36 side.
Accordingly, the inner transfer device 40 moves up and down as the shaft portion 43e, which is a rotation shaft, rotates. By performing such an operation, one of the two wafers transferred into the processing chamber 16 by the outer transfer device 30 is moved away from the transfer chamber 12 from above the first processing unit 36. It can be transported and placed on the second processing unit 38.
Since the inner transfer device 40 becomes high temperature (about 200 ° C.) due to heat radiation from the first processing unit 36 and the second processing unit 38, for example, alumina ceramic, quartz, SiC ( It is preferable to form from silicon carbide), AlN (aluminum nitride) or the like. By forming, for example, alumina ceramics having a smaller thermal expansion coefficient than that of metal parts, it is possible to prevent deterioration in conveyance reliability due to deflection due to thermal deformation. However, metal parts are used at the base of the inner transfer device 40 for position / level adjustment.

  The first processing unit 36 and the second processing unit 38 are fixed to the apparatus main body 11 by a fixing member (not shown) in the processing chamber 16. Three first holding pins 39a penetrate the outer periphery of the first processing unit 36 in the vertical direction, and the first holding pins 39a move up and down to raise and lower the wafer 1 substantially horizontally. Three second holding pins 39b penetrate the outer periphery of the second processing unit 38 in the vertical direction, and the second holding pins 39b move up and down to raise and lower the wafer 1 substantially horizontally. Therefore, the wafer 1 conveyed by the outer transfer device 30 via the gate valve 35 is placed on the holding table 37 via the holding pins 39a and 39b. That is, when the motor rotates and reversely rotates, the first holding pin 39a and the second holding pin 39b move in the vertical direction.

5 and 6 show an outline of a wafer transfer flow in the processing chamber 16.
5 (a) to 5 (d) and FIGS. 6 (e) to (h), the upper diagram is a top view of the processing chamber 16, and the lower diagram is a diagram depicting the cross section of the upper diagram, and is an explanatory diagram. .
In the figure below, one of the holding pins 39a is provided at a location near the gate valve 35 in the first processing section 36. This is for convenience of explanation. Actually, as shown in the upper diagram, the holding pin 39a is provided at a location near the gate valve 35 in the first processing unit 36, that is, at a location where the outer transfer device 30 waits as shown in the upper diagram of FIG. Is not provided.
In the following description, the operation of each part constituting the two-wafer semiconductor manufacturing apparatus 10 is controlled by the controller 84.
First, the inside of the processing chamber 16 is decompressed to the same pressure as the transfer chamber 12.

(Step 1 FIG. 5A)
The gate valve 35 is opened, and the first holding pin 39a of the first processing unit 36 and the second holding pin 39b of the second processing unit 38 are raised. The inner transfer device 40 stands by on the second processing unit 38 side and ascends together with the first holding pin 39a and the second holding pin 39b.

(Step 2 FIG. 5B)
The inner transfer device 40 moves substantially horizontally to the first processing unit 36 side as the shaft portion 43e rotates. At this time, the notch 43 b of the inner transfer device 40 faces the gate valve 35.

(Step 3 FIG. 5 (c))
The outer transfer device 30 moves from the transfer chamber 12 to the processing chamber 16 via the gate valve 35 while simultaneously transferring the two wafers 1 and 1 placed on the upper finger 32a and the lower finger 32b, Stops above the processing unit 36. At that time, the inner transfer device 40 stands by at a height position between the upper finger 32a and the lower finger 32b of the finger assembly 32.

(Step 4 FIG. 5D)
In a state where the outer transfer device 30 does not operate as it is, the first holding pins 39a of the first processing unit 36 are raised, and the wafer placed on the lower finger 32b is placed on the first holding pins 39a. Further, as the inner transfer device 40 moves up, the wafer placed on the upper finger 32 a is placed on the claw portion 43 c of the inner transfer device 40.

(Step 5 FIG. 6 (e))
The outer transfer device 30 returns into the transfer chamber 12.

(Step 6 (f) in FIG. 6)
The inner transfer device 40 moves substantially horizontally to the second processing unit 38 side when the shaft 43e rotates while the wafer 1 is mounted.
The gate valve 35 is closed.

(Step 7 Fig. 6 (g))
The shaft portion 43e is lowered, and the inner transfer device 40 moves downward in the outer periphery of the second processing unit 38.
Since the inner transfer device 40 stands by in the processing chamber 16 even during wafer processing, the flow of processing gas (for example, O2 radicals) supplied from above the second processing unit 38 is obstructed, and the wafer surface There is a risk of worsening the uniformity of the inside. Therefore, it moves to a height that does not hinder the gas flow on the outer periphery of the second processing unit 38.

(Step 8 FIG. 6 (h))
The first holding pins 39 a of the first processing unit 36 and the second holding pins 39 b of the second processing unit 38 are lowered substantially simultaneously while holding the wafer 1 substantially horizontally, and the wafer 1 is placed on the holding table 37. That is, the wafers are lowered so that the distances between the wafers and the holding tables corresponding to the wafers are equal to each other. This is to make the thermal effects on the wafers of the first processing unit 36 and the second processing unit 38 the same.
By making the thermal effect the same, for example, the ashing rate of each wafer can be made uniform. It is not necessary to have exactly the same heat effect, and there may be an error as long as the ashing rate is uniform. The error is, for example, about 2 seconds.
Instead of lowering the first holding pin 39a and the second holding pin 39b substantially at the same time to make the thermal effect the same, the heaters may be individually controlled.
In this embodiment, the holding pin 39 is lowered, but the holding base 37 may be moved up and down.

  Thereafter, gas is supplied into the processing chamber 16 to generate plasma (ashing processing). After the substrate processing, the reverse sequence is executed to carry out the processed wafers 1 and 1.

By the way, in the above two-wafer semiconductor manufacturing apparatus 10, the outer transfer apparatus 30 has one load lock chamber 14a or 14b in which 25 wafers 1 are stocked (hereinafter, described with reference to the load lock chamber 14a). Since the wafers 1 are sequentially taken out two by two, the outer transfer device 30 takes out only one at the end (the 13th time).
On the other hand, since the processing chamber 16a is set to process two wafers 1 at a time, the outer transfer device 30 cannot transfer only one wafer 1 to the processing chamber 16a.

Therefore, in the present embodiment, it is assumed that the fractional wafer can be properly formed by mounting the fraction processing program for executing the flow shown in FIG.
That is, the fraction processing program determines that, for a selected process job, an odd number of wafers can be processed by the same process recipe in the same processing chamber 16a for the last one and the first one of another process job. In this case, the process jobs are connected, and the last one and the first one are combined into two, and the outer transfer device 30 is carried into the processing chamber 16a.

FIG. 7 is a flowchart of the fraction processing program.
25 wafers are transferred from the carrier (not shown) supplied to the EFEM 18 in advance to the load lock chamber 14a by the wafer transfer device in the EFEM 18 (first step S1).
It is determined whether “unprocessed wafer is in the load lock chamber” (second step S2).
In the case of “Yes”, it is determined whether “the target wafer is the last (25th) wafer” (third step S3).

In the case of “the last one”, it is determined whether “can be connected to another process job” (fourth step S4). That is, it is determined whether “the process job of the second load lock chamber 14b is already in a processable state (before the processing order of the last wafer of the process job of the first load lock chamber 14a is reached)”.
If two sheets are processed for 25 carriers, the last one becomes a fraction. At this time, if the next carrier cannot be put in time, the processing is performed as it is.
This “in time” condition is that, after the last wafer of the preceding process job is started to be transferred from the load lock chamber 14a to the processing chamber 16a, the subsequent process job is evacuated in the second load lock chamber 14b, and the pressure is reduced. It must be possible to transport with.

If “can be connected”, it is determined whether “process recipe names match” (fifth step S5). That is, it is determined whether the process recipe name of the last wafer 1 in the first load lock chamber 14a matches the process recipe name of the first wafer 1 in the second load lock chamber 14b.
One process recipe is selected for one process job. The process recipe of the preceding process job and the subsequent process job must match. Whether or not they match can be determined from the selected process recipe name (unique in the system).

In the case of “match”, it is determined whether “VP (Variable Parameter) is not changed between two process jobs” (sixth step S6). That is, it is determined whether or not parameters such as temperature, pressure, and gas flow rate are changed between the first processing chamber 16a and the second processing chamber 16b. Alternatively, it is determined whether or not the VP change contents completely match.
Since the contents of the process recipe can be changed from the host controller, if the VP values are different even if the process recipes match, a wafer to be processed in the second processing chamber 16b cannot be carried into the first processing chamber 14a. .

In the case of “None”, the process proceeds to the seventh step S7, the outer transfer device 30 is controlled, and the fraction accumulation transfer flow shown in FIG. 8 is executed as follows.
As shown in FIG. 8A, the outer transfer device 30 transfers the wafer 1 of the uppermost mounting portion 28, which is the 25th stage of the support base 20 installed in the first load lock chamber 14a. Scrape with the lower finger 32b.
In FIG. 8A, the processed wafers 1A are held on the placement units 28 other than the uppermost stage.
Subsequently, the outer transfer device 30 moves the finger assembly 32 to the second load lock chamber 14b as shown in FIG. 8B while holding the wafer 1 with the lower finger 32b, and the second load The wafer 1 is scooped by the fingers 1 2 a on the wafer 1 of the lowermost stage mounting portion 28, which is the first stage of the support 20 installed in the lock chamber 14 b.
In FIG. 8B, the unprocessed wafers 1 are also held on the mounting portions 28 other than the lowermost stage.
Next, the outer transfer device 30 moves the finger assembly 32 to the first processing chamber 16a as shown in FIG. 8C while holding the wafers 1 and 1 by the upper finger 32a and the lower finger 32b. And stop above the first processing unit 36.
The operation after the finger assembly 32 is stopped above the first processing unit 36 is the same as that in steps 4 to 8 described above.

In turn, “not the last one” is determined in the third step S3, “impossible” in the fourth step S4, “mismatch” in the fifth step S5, and “present” in the sixth step S6. In the case, the process proceeds to the eighth step S8.
In the eighth step S8, if it is determined in the third step S3 that “it is not the last one”, the outer transfer device 30 moves the upper and lower wafers 1 and 1 to the upper finger 32a and the lower finger 32b. At the same time, the normal conveying process is performed.
However, if it is determined as “impossible” in the fourth step S4, if it is determined as “mismatch” in the fifth step S5, or if it is determined as “present” in the sixth step S6, the outer transfer is performed. The apparatus 30 executes a fraction transfer process in which only one wafer 1 is scooped by the lower finger 32b.

  When the fraction accumulation transfer processing step S7 or the uncontrolled transfer processing step S8 is executed, a process recipe is executed in the ninth step S9, and the plasma generation (ashing process) is performed on two or one wafer 1 as described above. ) Is given.

When the ninth step S9 ends, the process proceeds to a tenth step S10. In the tenth step S10, the outer transfer device 30 returns the processed wafer 1A to the original support table 20 of the load lock chambers 14a and 14b by the operation opposite to the operation of FIG.
That is, when passing through the fraction accumulation transfer processing step S7, the outer transfer device 30 picks up the processed wafer 1A picked up by the upper finger 32a, and the lowermost stage mounting portion of the support base 20 of the second load lock chamber 14b. Returning to 28, the processed wafer 1A picked up by the lower finger 32b is returned to the uppermost stage mounting portion 28 of the support base 20 of the first load lock chamber 14a.
In the case of passing through the uncontrolled transfer processing step S8, the outer transfer device 30 removes the processed wafer 1A picked up by the lower finger 32b from the uppermost stage mounting portion of the support base 20 of the first load lock chamber 14a. Return to 28.
When the tenth step S10 ends, the process returns to the second step S2, and the above routine is repeated.

  If it is determined in the second step S2 that there is no unprocessed wafer, the process proceeds to an eleventh step 11. In the eleventh step 11, the outer transfer device 30 transfers the 25 processed wafers 1A from the first load lock chamber 14A to the carrier.

  According to the embodiment, the following effects can be obtained.

(1) The last one in the first load lock chamber and the first wafer of the process job waiting in turn in the second load lock chamber are transferred together to the processing chamber, so that they are the same as in normal processing. Since two wafers can be processed at the same time, the uniformity between wafers (uniformity between wafer surfaces) in the two-wafer semiconductor manufacturing apparatus can be maintained.

(2) This is a case where a fraction is generated by transferring the last sheet of the first load lock chamber and the first wafer of the process job waiting in the second load lock chamber to the processing chamber. However, since two wafers can be processed at the same time as in normal processing, the throughput of the two-wafer semiconductor manufacturing apparatus can be improved.

  Needless to say, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

  For example, the present invention is not limited to a film forming process for forming an insulating film, a metal film, and a semiconductor film on a wafer, but includes an oxidation process, a diffusion process, a carrier reflow after ion implantation, a reflow for annealing, an annealing process, etc. It can be applied to general substrate processing.

  Further, the present invention can be applied not only to a substrate processing apparatus that performs processing on a wafer for forming an IC but also to general substrate processing apparatuses such as a substrate processing apparatus that performs processing on a glass substrate of an LCD device.

It is a typical plane sectional view showing the 2 sheet semiconductor manufacturing device which is one embodiment of the present invention. It is the longitudinal cross-sectional view. It is a perspective view which shows the processing chamber. It is a top view which shows the inner side transfer apparatus periphery at the time of the wafer process. It is each typical top view and each longitudinal cross-sectional view which show a wafer transfer flow. It is each typical top view and each longitudinal section showing the continuation of a wafer transfer flow. It is a flowchart of a fraction processing program. It is each typical side view showing a fraction accumulation conveyance flow.

Explanation of symbols

1 Wafer (substrate)
1A Processed wafer 14a First load lock chamber 14b Second load lock chamber 16a First process chamber 16b Second process chamber 20 Support base 28 Placement unit 30 Outside transfer device (second transfer means)
32 Finger assembly 32a Upper finger 32b Lower finger 36 First processing section

Claims (1)

A plurality of processing chambers for processing the substrate;
A first transfer chamber provided with a first transfer means for transferring a substrate to each processing chamber;
A second transfer chamber provided with a second transfer means for transferring a substrate in an atmospheric pressure state;
A depressurizable spare chamber connecting the first transfer chamber and the second transfer chamber;
In the substrate processing apparatus provided with the control means for controlling the transfer of the first transfer means and the second transfer means between the substrate storage means storing a plurality of substrates and the processing chamber,
In the case where processing is continuously performed across a plurality of the substrate storage means according to the operation recipe assigned to the substrate placed in the slot provided in the substrate storage means, the first substrate storage means A substrate processing apparatus for simultaneously processing a last substrate placed and a first substrate placed in the second substrate storage means.

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