JP2009071041A - Vacuum processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum processing apparatus capable of conveying two kinds of substrates from cassette carriers, with each being suited thereto with a common device. <P>SOLUTION: The vacuum processing apparatus includes a plurality of cassette carriers 1, having different kinds of shapes, an automatic loader 20 for carrying substrates stored in the cassette carriers 1, and a cassette stage 30 for setting the cassette carriers 1. The apparatus also comprises a discrimination switch 50 for discriminating the kind of the cassette carrier 1, when a cassette carrier 1 is set into the cassette stage 30. This apparatus further includes a substrate convey arm 13 of the automatic loader 20 with the substrate receiving initial height changeable, based on the kind of the cassette carrier 1 discriminated by the discrimination switch 50. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vacuum processing apparatus used in a semiconductor device manufacturing process. In particular, the present invention relates to a vacuum processing apparatus that transports a thin film substrate and performs a film forming process in manufacturing a power element semiconductor called a power device or a mounting wiring process.

  Conventionally, a standard Si substrate has a thickness of about 750 μm, and such a semiconductor substrate does not cause warping or sagging of the substrate due to partial contact support during transportation, and many semiconductor manufacturing and electronic components It has been widely used for research and mass production in manufacturing.

  In recent years, with the development of the IT industry, application of power devices and mounting wiring boards has been activated. In such applications, it has become essential to reduce the substrate thickness from the conventional standard substrate thickness. As a background for reducing the thickness of the substrate, there was the following necessity. In the case of a power device, it has become necessary to make the substrate thickness as thin as possible for the purpose of lowering resistance in order to form a transistor perpendicular to the substrate, that is, to allow current to flow in the substrate thickness direction.

  On the other hand, in the mounting wiring technology such as WLP (Wafer Level Package), as represented by various portable mobile devices, in order to ensure the compactness of the product, the devices used should be mounted as thin and small as possible. Has been required.

  However, in the transport of such a thin substrate (generally having a thickness of 300 to 400 μm or less and targeted to a thickness of 30 to 50 μm), the transport is caused by dripping (bending) or warping of the substrate. There is a problem.

  FIG. 5 shows a general multi-chamber vacuum processing apparatus as a first background art example. This vacuum processing apparatus includes a transfer chamber 42 that forms a space for transferring a substrate, and vacuum processing chambers 24 a, 24 b, 24 c and a load lock chamber 41 that are respectively disposed on four side surfaces of the transfer chamber. A transfer robot 25 having a substrate transfer arm 43 is installed in the transfer chamber 42. An autoloader 20 for carrying the substrate 2 accommodated in the cassette carrier 1 into the apparatus is installed at a location corresponding to the outer surface of the load lock chamber 41. The autoloader 20 includes a cassette stage 30 for setting a plurality of cassette carriers 1, an autoloader robot 21 having a substrate transfer arm 13, and an aligner 40 for aligning the substrate 2.

  Furthermore, the conveyance path | route of the board | substrate 2 in the said vacuum processing apparatus is explained in full detail based on FIG. In addition, the arrow in FIG. 5 shows the typical conveyance path | route of the board | substrate 2. FIG.

  The substrates 2 stored in the cassette carrier 1 are conveyed to the aligner 40 one by one by the vacuum chuck method by the substrate transfer arm 13 of the autoloader robot 21. The aligner 40 centers the substrate 2 and aligns the orientation of the substrate 2 in the rotational direction based on a reference position called OF (Orientation Flat) or notch. Thereafter, the substrate 2 is transferred to the load lock chamber 41 by the substrate transfer arm 13.

  Normally, in the case of a standard substrate storage pitch, 25 cassettes 2 are stored in multiple stages in the cassette carrier 1, and 25 shelves are secured in the load lock chamber 41. As described above, when all the 25 substrates 2 that have been aligned and centered are placed on the shelf of the load lock chamber 41, the gate valve (not shown) is closed and the load lock chamber 41 is shut off from the atmosphere. It is evacuated. When the evacuation is completed, a gate valve (not shown) between the load lock chamber 41 and the transfer chamber 42 is opened. Then, the substrate transfer arm 43 of the transfer chamber 42 sets the substrates 2 stored in the load lock chamber 41 one by one on the stage 26 in the vacuum processing chamber 24a, and the substrate 2 is subjected to film formation and etching.

  In the case of forming a multilayer film, the substrate 2 is set in order in the other vacuum processing chambers 24b and 24c as indicated by arrows in the figure, and the processing is continued. Return to LL shelf.) When 25 sheets of this work are completed, the load lock chamber 41 is isolated from the transfer chamber 42 by a gate valve, and then opened to the atmosphere. Finally, the processed substrate 2 is collected in the cassette carrier 1.

  FIG. 6 is a diagram of a cassette carrier applied to the vacuum processing apparatus, and FIG. 6A shows a case where a standard substrate (when there is no warpage) 2a is stored in the standard cassette carrier 1a. In this case, the cassette carrier 1a has a standard shelf pitch of about 6 mm. On the other hand, the cassette carrier shown in FIG. 6B is called a double-pitch carrier 1b, and considering the slack of the thin substrate 2b, the shelf pitch is doubled compared to the standard cassette carrier 1a. Yes. In this case, the number of substrates stored is 13 for the double-pitch carrier 1b compared to the standard number of 25 substrates, and the number of stored substrates is reduced. Incidentally, in the case of a 100 μm thick substrate, it was confirmed by experiments that the maximum warpage amount is about 2 mm.

  On the other hand, in order to prevent warping and bending of the substrate, a thin substrate is attached to a support material (a thermally stable substrate such as quartz or Pyrex) with no warp, using an adhesive. A method of carrying is also put into practical use. In this case, since there is no warping or bending, the standard cassette carrier 1a is used to increase the storage efficiency. FIG. 7 shows a case where a thin substrate is stored in an LL shelf mounted on an elevator mechanism of a load lock chamber. Also in this case, similarly to FIGS. 6A and 6B showing the cassette carrier, when two kinds of substrates are mounted, the result is as shown in FIGS. 7A and 7B. That is, in the case of a standard thickness Si substrate or when the thin substrate 2b is bonded to a support base such as quartz, the shelf 3a has a standard pitch. On the other hand, in the case of the thin substrate 2b, the pitch of the shelves 3b is twice that of the standard pitch shelves 3a. In the case of a thin substrate, since devices such as wiring are usually formed on the side opposite to the upper surface, a coating 4 is applied to the shelf 3b so as to prevent scratches at the time of contact. As this coating material, materials such as polytetrafluoroethylene and polyimide are widely used in vacuum.

  In the method of attaching the substrate to the support base, the thin substrate 5 is bonded to the quartz support base 7 with an adhesive 10 as shown in FIG. This method is generally referred to as HWSS (Hard Wall Support System). As described above, in HWSS, the cost for manufacturing the device is increased by the necessity of the preceding and following processes. However, since the problem of warpage and bending when the film is formed on the substrate is solved, the transport reliability is improved.

  On the other hand, in the above-described film formation on the HWSS substrate (hereinafter abbreviated as the HWSS substrate), there is a restriction on the upper limit of the substrate temperature at the time of film formation from the heat-resistant temperature of the adhesive to adhere the thin substrate to the support base. There is a problem that arises. In order to solve this problem, the HWSS substrate is fixed to the holder by a mechanical clamp or ESC (electrostatic chuck), the back of the HWSS substrate is filled with gas, the substrate is cooled using the gas as a medium, and the substrate being formed It is necessary to suppress the temperature rise.

  However, in the mechanical clamp method (not shown), the end of the support base such as the quartz substrate is easily broken, and there is an unstable factor in the support method. On the other hand, the ESC (electrostatic chuck) method has better backside gas sealing efficiency than the mechanical clamping method. As a result, there are advantages in that the absorption efficiency of plasma heat during film formation is good, and above all that the contact surface with the substrate surface can be made small, so that damage and particle generation due to scratches are suppressed. FIG. 9 shows a cross-sectional view when a HWSS substrate is attracted to a general ESC (electrostatic chuck).

  According to FIG. 9, the HWSS substrate 7 is placed on the ESC stage 8, a voltage is applied to the ESC built-in electrode, and the HWSS substrate 7 is held by electrostatic coulomb force due to induced charges. In this ESC method, the ESC surface (contact surface with the substrate) is formed by a number of convex portions called embossing 11. A method of improving the heat conduction efficiency using a gas as a medium by bringing such a portion into contact with the substrate and filling the gap 12 between the convex portions with gas is common. There is also a type (not shown) that does not have such convex protrusions and has a planar shape and does not introduce gas into the back surface.

  This ESC method has many advantages as described above. However, when a thick material such as an HWSS substrate is adsorbed, an ESC built-in electrode is used to generate an electrostatic attraction force using the inter-electrode coulomb force. A structure capable of supplying a voltage several times higher than usual was required. For this reason, it is necessary to devise an electrode structure in which the supplied power has a withstand voltage.

  In any case, in the use of the mounting wiring board and the device of the power device system, the cassette carrier 1 suitable for each of two types of boards, that is, a board having a bend (thin board) and a board having no bend (such as a HWSS board) is used. It is necessary to prepare and carry the substrate.

  In the method of transporting a thin substrate, it is necessary to make the shelf pitch 2 to 3 times that of the standard cassette carrier in consideration of the drooping of the substrate in the cassette carrier. In addition, since the amount of bending of the substrate differs when the thickness of the substrate is different, it is necessary to adjust the feed pitch in the vertical direction of the substrate transfer arm in accordance with the substrate to be transferred. On the other hand, a standard cassette carrier is used in a system for transporting a Si substrate or a HWSS substrate having a standard thickness, but it is necessary to increase the supply power applied to the ESC stage that holds the substrate more than usual. These methods have advantages and disadvantages and need to be used properly depending on the device type. Conventionally, in order to support such a plurality of cassette carriers, it is necessary to prepare a dedicated loader for each type of cassette carrier or to change one loader every time the type of cassette carrier is changed. . The former costs more than twice as much as when dealing with one type of cassette carrier. In the latter case, remodeling took time and was an obstacle to production efficiency.

  SUMMARY OF THE INVENTION In view of the problems of the background art described above, an object of the present invention is to provide a vacuum processing apparatus capable of transporting a substrate from each cassette carrier having a different storage shape suitable for each of the two types of substrates using a common device. It is in.

  The vacuum processing apparatus of the present invention includes a plurality of types of cassette carriers having different shapes for storing substrates in multiple upper and lower stages, and a loader for carrying the substrates stored in the cassette carrier. This vacuum processing apparatus includes a cassette stage for setting a cassette carrier, and a discriminating means for discriminating the type of the cassette carrier based on the shape of the cassette carrier when the cassette carrier is set on the cassette stage. The vacuum processing apparatus includes a substrate transfer arm provided in the loader, the substrate transfer arm changing a substrate receiving initial height based on the type of the cassette carrier determined by the determination unit.

  According to the present invention, a substrate can be transported by a common apparatus from a plurality of types of cassette carriers that are respectively adapted to a substrate that is bent or warped and a substrate that is not.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is used for the same thing as the component demonstrated in the column of background art.

  FIG. 1 shows a positional relationship between various cassette carriers and a substrate transfer arm of an autoloader according to a first embodiment of the present invention. FIG. 2 shows various cassette carriers.

  FIG. 1A shows a cross section of the standard cassette carrier 1a in which the HWSS substrate 2a or the standard substrate is stored in multiple stages. On the other hand, FIG. 1B shows a cross-sectional view of a state in which thin substrates 2b are accommodated in multiple stages in a double pitch carrier 1b. In these drawings, reference numeral 13 denotes an autoloader substrate transfer arm.

  The substrate transfer arm 13 is inserted in the gap between the substrates with respect to the carriers 1a and 1b, and scoops and holds the substrate. When transporting the HWSS substrate 2a of the standard cassette carrier 1a, the substrate transport arm 13 is first inserted between the uppermost substrates of the standard cassette carrier 1a. This initial insertion position is preset as the substrate transfer initial height of the substrate transfer arm 13. Further, the vertical movement pitch from the initial substrate transfer height of the substrate transfer arm 13 is also set in advance in accordance with the shelf pitch of the standard cassette carrier 1a. On the other hand, when the thin substrate 2b of the double-pitch carrier 1 is transported, the thin substrate 2b is drooping, so that the amount A is lower than the initial substrate delivery height of the HWSS substrate 2a in consideration of the bending amount d. The height of the substrate transfer arm 13 is adjusted. Then, the substrate transfer arm 13 is inserted into the double pitch carrier 1 at this height, and the HWSS substrate 2b is scooped up. In order to scoop up the lower substrate 2b, the substrate transfer arm 13 is moved downward and inserted at a moving pitch twice that of the standard cassette carrier 1a.

  Thus, it is necessary to adjust the initial insertion position (substrate transfer initial height) and movement pitch of the substrate transfer arm 13 of the autoloader according to the two types of carriers and the types of substrates. For this reason, in the background art of the present invention, it is necessary to reset the initial insertion position and movement pitch of the substrate transfer arm 13 of the autoloader each time the type of the cassette carrier is changed. On the other hand, the present invention automatically changes the initial insertion position and the movement pitch.

  Specifically, as shown in FIG. 1, a discrimination switch 50 for discriminating the type of the set carrier is installed at the lower part of the setting place of the cassette stage 30 for setting the cassette carriers 1a and 1b.

  The standard cassette carrier 1a is provided with a blocking plate 55 at the bottom. Therefore, when the standard cassette carrier 1a is set on the cassette stage 30, the blocking plate 55 blocks the signal 53 (emitted light) from the light emitting unit 51 of the discrimination switch 50, and the reflected signal 54 (reflected light) therefrom is generated. It is detected by the detection unit 52. On the other hand, since the blocking plate 55 is not provided at the bottom of the double pitch carrier 1 a, when the double pitch carrier 1 b is set on the cassette stage 30, the light of the light emitting unit 51 is not blocked and a signal is sent to the detection unit 52. not enter. The carrier type is determined based on the ON / OFF state of the detection unit 52 in the determination switch 50. Then, according to the determination signal (ON signal, OFF signal) at this time, the setting of the Z-axis height (vertical height) and the vertical movement pitch of the substrate transfer arm 13 of the autoloader robot 21 is changed. Thereby, conveyance adjustment of two types of board | substrates 2a and 2b can be performed. In addition, it is not limited to two types of substrates, and if the initial insertion position and movement pitch of the substrate transfer arm 13 are set in advance according to three or more types of substrates, a plurality of types of cassette carriers adapted to various substrates can be used. It is possible.

  Next, the vacuum processing apparatus of the present embodiment will be described with reference to FIG. FIG. 3 is a diagram in which components of the present invention such as the discrimination switch 50 are added to the vacuum processing apparatus according to the background art shown in FIG. As shown in the figure, a discrimination switch 50 is installed in the cassette stage 30 where each cassette carrier 1 is set, and a signal line 61 from each discrimination switch 50 is connected to the controller 60. Further, the controller 62 and the autoloader robot 21 are connected by a signal line 62. A signal line 61 connecting each discrimination switch 50 to the controller 60 transmits an ON signal and an OFF signal from the discrimination switch detector 50 corresponding to the set location of each carrier.

  Therefore, when the cassette carrier 1 is set on the carrier stage 20, an ON signal or an OFF signal corresponding to the cassette carrier type is transmitted to the controller 60 through the signal line 61. Then, the controller 60 transmits a control signal based on one of the signals to the autoloader robot 21 via the signal line 62, and changes the initial insertion position and the vertical movement pitch of the substrate transfer arm 13 set in advance. That is, the controller 60 receives the initial insertion position information and the vertical movement pitch information of the substrate transfer arm 13 according to the cassette carrier type as a control signal output in response to reception of the ON signal or OFF signal from the discrimination switch 50. Stored.

  Further, the controller 60 recognizes from which discrimination switch 50 at each carrier set location of the cassette stage 30 and transports the substrate with respect to the cassette carrier 1 at the location where the discrimination switch 50 transmitting the signal is provided. Transport by the arm 13 is performed. Therefore, it is preferable that the output of each discrimination switch 50 can be identified by changing it for each carrier set location.

  The carrier type discrimination result by the discrimination switch 50 is used to drive a mechanism for adjusting the vertical height of the shelf (LL shelf) of the load lock chamber 41 that isolates the transfer path to the processing chamber from the atmosphere. Also good. That is, the vertical height of the LL shelf may be adjusted based on the cassette carrier type determined by the determination switch 50.

  Next, another embodiment of the present invention will be described. FIG. 4 shows the relationship among the carrier cassette, the discrimination switch, and the substrate transfer arm in another embodiment of the present invention. In this example, the above-described vacuum processing apparatus is provided with measuring means for measuring the deflection amount of the substrate stored in the cassette carriers 1a and 1b. The measuring means includes a proximity sensor 70 which is a position detection sensor arranged at a setting position of the cassette stage 30 on which the cassette carriers 1a and 1b are set, and a detection for transmitting a signal from the proximity sensor 70 via the signal line 64. Device 71.

  The proximity sensor 70 is disposed so as to be close to the center position of the substrate stored in the lower part of the cassette carriers 1a and 1b. By the proximity sensor 70, the displacement of the substrate from the supported portion without bending is measured as the amount of bending. Here, the “supported portion of the substrate without deflection” refers to a portion of the substrate 2b supported by the shelf, and the amount of deflection is the amount of substrate displacement downward from this portion.

  The substrate transfer arm 13 has a function of correcting a substrate reception initial height (initial insertion position) set in advance for the reference cassette carrier 1a in accordance with the amount of deflection transmitted from the controller 60. Specifically, as shown in FIG. 4, the proximity sensor 70 is brought close to the center position of the substrate 2b below the cassette carrier 1a, and the amount of warpage of the substrate 2b is measured by the detector 71. The detection signal at this time is transmitted to the controller 60 through the signal line 64. The controller 60 transmits a control signal based on this signal (the amount of warpage of the substrate 2b) to the autoloader robot 21 via the signal line 62, and the initial insertion position of the substrate transfer arm 13 set in advance with respect to the cassette carrier 1a. Is corrected to correspond to the double pitch carrier 1b. According to this method, there is an effect that it is not necessary to set the initial insertion position of the substrate transport arm 13 for each type of cassette carrier as in the first embodiment.

  The amount of substrate deflection measured by such measuring means can be used not only for adjusting the arm conveyance of the autoloader robot 21 as described above, but also for adjusting other devices. For example, in the aligner 40, if the substrate hangs down on the aligner stage, the optical system may not be able to detect notches or OFs. In this case, it is possible to adjust the substrate recognition by the optical system using the substrate deflection amount measured as described above.

  By carrying the substrate in the vacuum processing apparatus of the present invention as described above, a plurality of cassette carriers, that is, a plurality of substrate types, can be carried without impairing productivity. Greatly contributes to productivity improvement.

It is the figure which showed the positional relationship of various cassette carriers and the board | substrate conveyance arm of an auto loader in the 1st Example of this invention. It is sectional drawing which shows the various cassette carriers of FIG. It is a top view which shows the structural concept of the vacuum processing apparatus of this invention. In another Example of this invention, it is a figure which shows the relationship between a carrier cassette, a discrimination means, and a board | substrate conveyance arm. It is a top view which shows the structural concept of the vacuum processing apparatus which concerns on the background art of this invention. It is sectional drawing which shows the cassette carrier which concerns on background art. It is sectional drawing which shows the load lock shelf (LL shelf) which concerns on background art. It is sectional drawing of the HWSS board | substrate which concerns on background art. It is an expanded sectional view of the ESC stage which concerns on background art.

Explanation of symbols

1 cassette carrier 1a standard cassette carrier 1b double pitch carrier 2 substrate 2a HWSS substrate 2b thin substrate 13, 43 substrate transfer arm 20 autoloader 21 autoloader robots 24a, 24b, 24c processing chamber 25 transfer robot 26 stage 30 cassette stage 40 aligner 41 load lock Chamber 42 Transfer chamber 50 Discriminating switch 51 Light emitting portion 52 Detection portion 55 Blocking plate 60 Controller 61, 62 Signal line 70 Proximity sensor 71 Detector

Claims (6)

In a vacuum processing apparatus having a plurality of types of cassette carriers having different shapes for storing substrates in multiple stages, and a loader for carrying the substrates stored in the cassette carrier,
A cassette stage for setting the cassette carrier;
Determining means for determining the type of the cassette carrier based on the shape of the cassette carrier when the cassette carrier is set on the cassette stage;
A substrate transport arm for transporting the substrate provided in the loader, the substrate transport arm changing a substrate receiving initial height based on the type of the cassette carrier determined by the determination means; A vacuum processing apparatus characterized by that.   The vertical height of the substrate transport arm is adjusted to a substrate receiving initial height preset for each type of the cassette carrier based on the type of the cassette carrier determined by the determination unit. The vacuum processing apparatus according to claim 1. A measuring means for measuring the amount of deflection of the substrate stored in the cassette carrier set on the cassette stage;
The vacuum processing apparatus according to claim 1, wherein a preset substrate receiving initial height is corrected in accordance with the amount of bending.   The measuring means has a position detection sensor that is brought close to the center position of the substrate stored in the lower part of the cassette carrier, and the position detection sensor allows the displacement of the substrate from the unsupported supported portion. The vacuum processing apparatus according to claim 3, wherein the vacuum processing apparatus measures the amount of bending. For each type of the cassette carrier, a storage pitch of the substrates stored in the cassette carrier is set,
The vertical movement pitch of the substrate transfer arm is changed to a movement pitch that matches the storage pitch of the substrate set for each type of the cassette carrier based on the type of the cassette carrier determined by the determination unit. The vacuum processing apparatus according to any one of claims 1 to 4.   Based on the load lock chamber that isolates the transfer path to the processing chamber from the atmosphere, the multistage shelves on which the substrate is placed in the load lock chamber, and the type of the cassette carrier determined by the determining means, The vacuum processing apparatus according to claim 1, further comprising a mechanism for adjusting a vertical height.

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