JP2009266866A - Adhesion device of material to be processed - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesion device which can paste up a material to be processed onto a tray without causing any damage on a mask formed on the surface of the material to be processed prior to plasma treatment. <P>SOLUTION: The adhesion device comprises a closed annular seal member 37 arranged above a substrate 14, a pressure balance sheet 38 arranged between the substrate 14 and the seal member 37 to come into surface-contact with the substrate 14, a lid 30B arranged on the seal member 37 to form a preload chamber between the pressure balance sheet 38 and the seal member 37, a gas inlet 36 for injecting gas into the preload chamber, and a clamp 30C for pushing the lid 30B to the seal member 37. Since the pressure balance sheet 38 comes into surface-contact with the substrate 14, a material to be processed can be pasted up onto a tray without causing any damage on a mask. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bonding apparatus for bonding a material to be processed to a tray prior to a plasma process in which etching, deposition (film formation), cleaning, or the like is performed on the surface of the material to be processed by plasma.

  In general, a material to be processed (hereinafter simply referred to as a substrate) such as a substrate to be plasma-treated is placed and fixed on a transfer tray for the convenience of handling. The tray is placed on a support base in a vacuum vessel provided in the plasma processing apparatus.

  When the plasma treatment is performed, the substrate temperature rises, so that a mask such as a photoresist formed on the substrate may be altered. In order to prevent this, the support table is cooled, and heat generated in the substrate is released from the support table via the tray.

  The support table and the tray can be sufficiently adhered by using a mechanical chuck, an electrostatic chuck, or the like. Therefore, there was no big problem in heat transfer between the support base and the tray. On the other hand, since the portability of the tray and the substrate is important, the above chucking method cannot be used. For this reason, the substrate cannot be sufficiently cooled even if the support base is cooled.

  Therefore, in order to solve this problem, the applicant of the present invention has a method of bonding the tray and the substrate with an adhesive member prior to the plasma treatment, and the bonding member without leaving bubbles between the tray and the substrate. The apparatus (processed material adhesion | attachment apparatus) which can do was proposed (refer patent document 1).

  In the processing material bonding apparatus, an adhesive member such as a foam-peelable sheet, a substrate, and a lid are sequentially placed on a tray, and the substrate is pressed by the lid and compressed air is supplied between the substrate and the lid. As a result, the tray and the substrate are bonded together with an adhesive member. An O-ring is disposed between the substrate and the lid so that the compressed air does not leak.

JP 2007-201404 A

  However, when the substrate to be processed is pressed with the lid, the O-ring is in direct contact with the surface of the substrate when the substrate is pressed with the lid, so that an O-ring pressing mark (O-ring mark) may remain on the mask on the substrate surface. It was. In particular, O-ring marks are likely to occur when a mask having a low hardness such as a photoresist is formed. Depending on the mask pattern, the mask may be deformed to adversely affect etching.

  It is also possible to suppress the occurrence of O-ring marks by optimizing the material of the O-ring and adjusting the pressure applied to the lid. However, depending on the mask material and the mask pattern, it may be difficult to perform them at the production site.

  The present invention has been made in order to solve the above-described problems, and the object of the present invention is to bond a material to be processed so that the material to be processed can be bonded to the tray without damaging the material to be processed. Is to provide a device.

An object-to-be-processed material bonding apparatus according to the present invention made to solve the above problems is as follows.
A processed material bonding apparatus for bonding a plate-shaped processed material placed on a tray to the tray,
a) a closed annular seal member disposed above the material to be treated;
b) a partial pressure sheet disposed between the material to be treated and the seal member and in surface contact with the material to be treated;
c) a lid disposed on the seal member and forming a pressurizing chamber between the pressure-dividing sheet and the seal member;
d) pressurizing means for injecting gas into the pressurization chamber;
e) presser means for pressing the lid against the seal member;
It is characterized by providing.

  It is desirable to use a heat peeling adhesive member for bonding the tray and the material to be processed. Here, the heat-peeling adhesive member refers to an adhesive member that loses its adhesive strength or loses its adhesive strength when it reaches a predetermined temperature or higher. For example, a foam release sheet or a foam release agent can be suitably used.

  The material to be treated targeted by the present invention may be of any kind, such as a semiconductor such as silicon or a compound, an insulator such as glass or resin, or a conductor such as metal. In addition, the shape of the wafer may be a large single-sheet wafer, or may be a large number of small chips.

  The terms “on the tray”, “above the material to be processed”, and “above the seal member” described above do not mean up and down with respect to the direction of gravity but merely indicate one direction. That is, for example, a case where the support base is disposed at the upper part in the direction of gravity, the tray is fixed to the lower surface by some method, and the material to be processed is bonded to the lower surface of the tray by the adhesive member is also included in the scope of the present invention. .

  According to the material to be treated bonding apparatus according to the present invention, the partial pressure sheet is in surface contact with the material to be treated, so that the material to be treated can be adhered to the tray without damaging the mask.

  At this time, even if the pressure applied to the seal member from the lid is biased by mechanical pressing, the pressure is dispersed without being concentrated at a specific place by the pressure dividing sheet, and the bias is corrected. Therefore, a uniform pressure can be applied to the material to be processed from the partial pressure sheet.

  One Embodiment of the to-be-processed material adhesion | attachment apparatus which concerns on this invention is described using FIGS. 1-4. FIG. 1 is a vertical cross-sectional view of the workpiece bonding apparatus 30. The bonding apparatus 30 includes a mounting table 30A on which the tray is mounted, a lid 30B that covers the mounting table 30A, and a clamp 30C that stacks and fixes the mounting table 30A and the lid 30B.

  FIG. 2 is a top view of the mounting table 30A. As shown in FIGS. 1 and 2, a central portion 31 </ b> A that is one step lower than the surroundings is provided on the upper surface of the mounting table 30 </ b> A in order to mount the tray. Thus, when the mounting table 30A is covered with the lid 30B, the exhaust chamber 31 is formed between them. The discharge port 33 for discharging the air in the exhaust chamber 31 is provided at a higher position around the central portion 31A. In addition, an exhaust chamber O-ring 34 is provided around the central portion 31A to keep the exhaust chamber 31 airtight.

  FIG. 3 is a bottom view of the lid 30B. As shown in FIGS. 1 and 3, a plurality of recesses 35 are formed on the lower surface of the lid 30 </ b> B. A gas inlet 36 for injecting a gas such as nitrogen is provided on the upper surface of each recess 35. A seal member (O-ring) 37 is provided around each recess 35. With such a configuration, a pressurizing chamber is formed between the lid 30 </ b> B, the sealing member 37, and a partial pressure sheet 38 described later.

  FIG. 4 is an enlarged view of the vicinity of the recess 35 in a state where the tray 15A and the substrate 14 are sandwiched between the mounting table 30A and the lid 30B. The tray 15A is a disk having substantially the same size as the central portion 31A of the mounting table 30A, and a recess 32 is provided on the upper surface thereof at a position directly below the concave portion 35 of the lid 30B. The substrate 14 is placed in each recess 32 via an adhesive member 16 such as a heat peeling adhesive member. A mask such as a photoresist or SiO2 is provided on the upper surface of the substrate 14 (not shown). Between each substrate 14 and the sealing member 37, a pressure dividing sheet 38 having a flat lower surface is disposed. The partial pressure sheet 38 is sized to cover at least the entire surface of the substrate 14. Note that, as shown in FIG. 5, the plurality of substrates 14 may be simultaneously covered with a single pressure dividing sheet 38. Since the partial pressure sheet 38 is in direct contact with the substrate 14, the surface thereof is a clean surface free from dust and the like.

  The material of the partial pressure sheet 38 includes polyester resin, nylon resin, acrylic resin, vinyl chloride resin, silicone resin or fluororesin, glass such as soda glass, crystal glass or silicate glass, aluminum silicon or gallium nitride, etc. Metals, semiconductors, ceramics such as aluminum oxide and silicon carbide can be used. These materials can be appropriately selected according to a mask material (for example, whether it is a photoresist) provided on the surface of the material to be processed, a mask pattern shape, a mask thickness, or the like. Among them, the resin has appropriate flexibility, can absorb minute irregularities on the surface of the material to be processed, and when a plurality of substrates 14 are covered with one partial pressure sheet 38, the resin is interposed between the substrates 14. Since the level | step difference which arises can be absorbed and the confidentiality of each pressurization chamber can be improved, it is preferable as a material of the partial pressure sheet 38. FIG.

  Depending on the material of the partial pressure sheet 38, a mask (particularly a photoresist mask) and the partial pressure sheet 38 may be attached. In such a case, minute unevenness is provided on the substrate 14 side of the voltage dividing sheet 38, or a layer 381 of another material (for example, SiO 2) is provided on the substrate side of the voltage dividing sheet 38 (see FIG. 6). The mask and the partial pressure sheet can be prevented from sticking by stacking sheets of different materials or using a partial pressure sheet in which two or more materials are mixed.

  The thickness of the partial pressure sheet 38 is preferably 0.01 to 5 mm, although it varies depending on the partial pressure sheet 38 or mask material, mask pattern shape, mask thickness, and the like. When the material of the partial pressure sheet 38 is a resin, the thickness is preferably 0.01 to 3 mm, and more preferably 0.01 to 0.25 mm, from the viewpoint that the above-described effects due to appropriate flexibility can be exhibited. A resin sheet having a thickness of 0.01 to 0.25 mm is generally called a film. When the partial pressure sheet 38 is a resin, if the partial pressure sheet 38 is too thin, O-ring marks tend to remain on the surface of the mask, particularly when the mask is a photoresist mask. Further, when pressure spots occur on the partial pressure sheet 38 for some reason, wrinkles are generated on the surface, and there is a tendency that wrinkle marks remain on the mask. Further, if the pressure dividing sheet 38 is thin, the workability is deteriorated and the confidentiality of the pressurizing chamber tends to be lowered. On the contrary, if the partial pressure sheet 38 is too thick, the substrate 14 is excessively pressed, and not only the mask but also the substrate 14 may be damaged.

  When the partial pressure sheet 38 is other than a resin, the thickness is preferably 0.1 to 5 mm, and more preferably 0.5 to 3 mm in that a high effect of preventing O-ring marks on the mask surface can be obtained. At this time, if the partial pressure sheet 38 is too thin, the partial pressure sheet 38 may be damaged and the confidentiality of the pressurizing chamber may not be maintained. On the contrary, if the partial pressure sheet 38 is too thick, the substrate is excessively pressed, and not only the mask but also the substrate may be damaged.

  The operation of the bonding apparatus 30 will be described with reference to FIGS. 1 and 4. First, the user inserts the tray 15A into the central portion 31A of the mounting table 30A, and places the substrate 14 in the recess 32 on the tray 15A via the adhesive member 16. Next, after the user places the partial pressure sheet 38 on the substrate 14, the user places the lid 30B on the mounting table 30A, and fixes both of them with the clamp 30C. Thereby, a pressurizing chamber is formed among the lid 30 </ b> B, the seal member 37, and the partial pressure sheet 38.

  Next, air is discharged from the discharge port 33 to reduce the pressure in the exhaust chamber 31. Further, nitrogen gas is supplied from the gas inlet 36 to increase the pressure in each pressurized chamber. The pressure of the gas supplied to the pressurizing chamber is preferably 0.2 MPa to 5 MPa in order to bond the substrate to the tray 15A while applying an appropriate force to the substrate 14 while applying an appropriate force to the substrate 14.

  After the tray 15A and the substrate 14 are fixed by the adhesive member 16, the exhaust from the discharge port 33 and the gas supply from the gas injection port 36 are stopped, and they are returned to atmospheric pressure. Thereafter, the clamp 30C is loosened, the lid 30B is removed from the mounting table 30A, the partial pressure sheet 38 is removed, and then the tray 15A is removed.

  As described above, in the bonding apparatus 30, by using the partial pressure sheet 38 in surface contact with the substrate 14, the mask can be prevented from being damaged, and the bonding state between the substrate and the tray is also improved.

  For the adhesion between the tray and the substrate, a comparison test of the bonding state was performed between the case where the processing material bonding apparatus according to the present invention was used (Example) and the case where the conventional processing material bonding apparatus was used (Comparative Example). In this test, the presence or absence of pressing marks on the photoresist mask on the substrate and the quality of adhesion between the substrate and the tray were evaluated. The tray used for the test has a diameter on which twelve 2-inch substrates can be placed, and a groove is provided on the surface for exhausting residual gas between the tray and the substrate. As the substrate, a sapphire substrate obtained by epitaxially growing gallium nitride (hereinafter referred to as a gallium nitride substrate) was used. A photoresist mask for forming an electronic circuit by plasma etching is provided on the surface of the gallium nitride substrate.

  In any of the examples and comparative examples, first, twelve heat-peeling adhesive members (Riva Alpha No. 3195M manufactured by Nitto Denko Corporation) having substantially the same diameter as the gallium nitride substrate were placed on the tray, and then the gallium nitride substrate. Was placed on each heat release adhesive member.

  Next, in the example, a polyester partial pressure sheet (thickness 0.5 mm) having the same diameter as the tray was placed on the gallium nitride substrate. A lid on which an O-ring was placed was placed on the gallium nitride substrate at a position corresponding to the outer periphery of the gallium nitride substrate, and the lid was fixed to the tray while pressing the O-ring. Then, while injecting nitrogen gas into the pressurizing chamber formed by the partial pressure sheet, O-ring and lid for about 1 minute (pressure 0.3 MPa), the space around the pressurizing chamber is decompressed for about 1 minute (pressure 8.0 × 10 -2 Pa) to bond the gallium nitride substrate to the tray. Then, after the pressure in the pressurizing chamber is returned to normal pressure, the tray is taken out from the bonding apparatus, the presence or absence of pressing marks in the resist mask of the 12 gallium nitride substrates, and the presence or absence of residual gas between the gallium nitride substrate and the tray Was visually evaluated. Note that since the sapphire substrate and gallium nitride have permeability, the presence or absence of residual gas between the substrate and the tray can be visually evaluated from the gallium nitride surface.

  In the comparative example, tests and visual evaluation were performed under the same conditions as in the examples except that the partial pressure sheet was not used.

  As a result, in the comparative example, both the press mark by the seal member and the residual gas between the substrate and the tray were visually confirmed. On the other hand, none was confirmed in the examples.

  In addition, this invention is not limited to above-described embodiment, For example, the following modifications are possible. In the above-described embodiment, seven sets of the concave portion 35, the gas injection port 36, and the seal member 37 are provided in one bonding apparatus 30, but the number thereof is arbitrary. The partial pressure sheet may be disposed at least under the seal member, and may be a donut-like member, for example.

The longitudinal section showing one embodiment of the processed material adhesion device concerning the present invention. The top view which shows the mounting base 30A of the adhesion | attachment apparatus 30. FIG. The bottom view which shows the lid | cover 30B of the adhesion | attachment apparatus 30. FIG. The enlarged longitudinal cross-sectional view of the recessed part 35 vicinity. The longitudinal cross-sectional view of the to-be-processed material adhesion | attachment apparatus 30 which shows a mode that the several board | substrate 14 is pressed with the sheet | seat of the partial pressure sheet 38 is shown. The enlarged longitudinal cross-sectional view of the recessed part 35 vicinity.

Explanation of symbols

14: Material to be treated (substrate)
15A ... Tray 16 ... Adhesive member 30 ... Process material bonding apparatus 30A ... Place 30B ... Cover 30C ... Clamp 31 ... Discharge chamber 31A ... Center part 33 of the mount ... Exhaust port 34 ... Exhaust chamber O-ring 35 ... Recess 36 ... Gas inlet 37 ... Sealing member 38 ... Partial pressure sheet

Claims (8)

A processed material bonding apparatus for bonding a plate-shaped processed material placed on a tray to the tray,
a) a closed annular seal member disposed above the material to be treated;
b) a partial pressure sheet disposed between the material to be treated and the seal member and in surface contact with the material to be treated;
c) a lid disposed on the seal member and forming a pressurizing chamber between the pressure-dividing sheet and the seal member;
d) pressurizing means for injecting gas into the pressurization chamber;
e) presser means for pressing the lid against the seal member;
An apparatus for bonding a material to be treated, comprising:   The processed material bonding apparatus according to claim 1, wherein the partial pressure sheet is a plate material made of resin, glass, metal, or ceramics.   The apparatus for bonding a material to be processed according to claim 1, wherein the partial pressure sheet is a film.   The said partial pressure sheet | seat consists of 2 or more types of materials, The to-be-processed material adhesion | attachment apparatus in any one of Claims 1-3 characterized by the above-mentioned.   The said partial pressure sheet | seat consists of two or more sheets, The to-be-processed material adhesion | attachment apparatus in any one of Claims 1-4 characterized by the above-mentioned.   The to-be-processed material adhesion | attachment apparatus in any one of Claims 1-5 with which the said partial pressure sheet is provided with the surface which covers the whole of two or more to-be-processed materials mounted on the said tray.   The processing material bonding apparatus according to claim 1, wherein a heat-peeling adhesive member is used for bonding the tray and the processing material.   The to-be-processed material adhesion | attachment apparatus in any one of Claims 1-7 provided with the pressure reduction means which pressure-reduces the space around the said pressurization chamber.

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