JP2006086479A - Thin film substrate holding method and semiconductor device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin film substrate holding method and a semiconductor device manufacturing method with which a thin film substrate may be processed in the same manner as an ordinary thick substrate. <P>SOLUTION: A holding material 4 and a thin film wafer W<SB>2</SB>are bonded via a bonding layer 3 provided along the external circumference of the thin film wafer W<SB>2</SB>and the thin film wafer W<SB>2</SB>is fixed to a holding material 4. The holding material 4 is provided with an aperture 4a communicated with the space between the thin film wafer W<SB>2</SB>and the holding material 4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for holding a thin film substrate, such as a thin semiconductor wafer, and a method for manufacturing a semiconductor device.

  Conventionally, conveyance / processing of a thinned wafer (for example, a thickness of 100 μm or less) is performed by attaching a holding material such as a resin or fiber sheet or glass substrate to the back surface or the surface of the thinned wafer. This is done while preventing cracking. For example, it is disclosed that a dicing adhesive sheet is attached to the back surface of a thinned wafer via a reinforcing sheet, and the thinned wafer is fixed to a ring frame via the dicing adhesive sheet. However, this technique has the following problems.

In the future, assuming a process that directly processes a thinned wafer for three-dimensional mounting of chips, not only one side of the wafer but also the formation of wiring on both sides, connecting the front and back sides A processing process such as wiring is required. When performing a double-sided process, the holding material present on the back or front side complicates the process or increases the number of steps. Also, each time the processing process is performed on the front and back surfaces of the thinned wafer, the holding material replacement process increases the cost and reduces the yield, such as the thinned wafer being damaged. Connected.
JP 2003-332267 A

  The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a thin film substrate holding method and a semiconductor device manufacturing method capable of handling the thin film substrate in the same manner as a normal thick substrate.

  According to one aspect of the present invention, the holding material and the thin film substrate are bonded to each other with an adhesive layer provided along the outer periphery of the thin film substrate, and the thin film substrate is fixed to the holding material. The method for holding a thin film substrate, wherein at least one of the holding material and the adhesive layer has an opening communicating with a space between the thin film substrate and the holding material. Is provided.

  According to another aspect of the present invention, the step of bringing the balloon made of an elastic body into contact with the thin film substrate and inflating the balloon to correct the warp of the thin film substrate, and bonding the thin film substrate with the corrected warp There is provided a method for holding a thin film substrate, comprising a step of fixing a holding material with a layer interposed therebetween.

  According to the method for holding a thin film substrate of one embodiment of the present invention, the thin film substrate can be handled in the same manner as a normal thick substrate, and the number of steps can be reduced. Moreover, according to the method for holding a thin film substrate of another aspect of the present invention, the thin film substrate can be handled in the same manner as a normal thick substrate while suppressing cracking of the thin film substrate.

  Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the same symbols are assigned to the same members.

(First embodiment)
Hereinafter, the first embodiment will be described. FIG. 1A to FIG. 1E are schematic views of a wafer thinning process and a thin film wafer holding process according to the present embodiment, and FIGS. 2 and 3 are diagrams in which the thin film wafer according to the present embodiment is fixed. FIG. 6 is a schematic plan view of a holding material in a damaged state. FIG. 4 is an enlarged view of the vicinity of the end portion on the adhesive layer side of the holding material according to the present embodiment, and FIGS. 5A and 5B are views in which the thin film wafer according to the present embodiment is fixed. It is a schematic diagram of the state which fixed the material to the stage.

As shown in FIG. 1A, first, a protective film 1 is formed on the surface (surface on the device side) of a wafer W ₁ made of Si, and the wafer W ₁ is vacuum chucked through the protective film 1. Fix to stage 2.

Then mechanically grinding the back surface of the wafer W _1, then, to improve the mechanical strength of the wafer W _1, dry polishing, chemical mechanical polishing to remove damages such as crystal defects to the wafer W ₁ (CMP ), Wet etching, dry etching or the like. As a result, the wafer W ₁ is thinned as shown in FIG. 1B (hereinafter, the “thinned wafer” is referred to as a “thin film wafer”). The thin film wafer W ₂ (thin film substrate) having a reduced thickness has a thickness of about 200 μm or less, preferably about 100 μm or less.

Thereafter, as shown in FIG. 1C, the holding material 4 is attached to the back surface of the thin film wafer W ₂ via the adhesive layer 3. The holding material 4 is formed in a ring shape as shown in FIGS. That is, the holding material 4 is formed with an opening 4 a communicating with the space between the thin film wafer W ₂ and the holding material 4. The opening 4a is, for example, to a fluid chemical solution or gas or the like for processing the thin film wafer W ₂ through the opening 4a into contact with the rear surface of the thin film wafer W _2, or a thin film wafer W ₂ in the thin film wafer W ₂ When penetrating through-holes are formed, it is used for flowing out chemicals, gases, etc. that have flowed in from the front surface side of the thin film wafer W ₂ through the through holes to the back surface side of the thin film wafer W ₂ .

Holding member 4 is preferably constructed of a material resistant to corrosion by fluids such as chemical solution or gas used in processing thin wafers W _2. Incidentally, the holding member 4 so as to form, instead of forming such materials, or such materials, the surface of the holding member 4 in a fluid such as chemical solution or gas used in processing thin wafers W ₂ On the other hand, it may be coated with a material having corrosion resistance. The holding material 4 can be made of, for example, Si such as single crystal Si or an Fe alloy (SUS310S) of a ferrite layer.

Retaining material 4, depending on the size of the thin-film wafer _{W 2} for holding, for example, it is possible to use a inner diameter 196 mm, an outer diameter of 204 mm, a thickness of 1 mm. End of the inner circumferential side and the thin film wafer W ₂ side of the holding member 4 is chamfered as shown in FIG.

Adhesive layer 3 is provided along the outer periphery of the thin film wafer W ₂ to and on the holding member 4, the thin film wafer W ₂ is adhered to the adhesive layer 3 in the outer peripheral portion of the thin film wafer W _2. In the present embodiment, the adhesive layer 3 is provided in a ring shape. The adhesive layer 3 does not have to be ring-shaped as long as it is provided along the outer periphery of the thin film wafer W _2. For example, the adhesive layer 3 includes a plurality of adhesive layers 3 divided as shown in FIG. Also good. In this case, an opening is formed between the adhesive layer 3 and the adhesive layer 3.

As shown in FIG. 4, in the adhesive layer 3, the length d ₁ in the direction orthogonal to the outer periphery of the thin film wafer W _{2 in} the adhesive layer 3 is larger than the length d ₂ in the thickness direction of the adhesive layer 3. . Further, the surface roughness of the back surface side of the thin film wafer W ₂ is ¼ or less of the thickness of the adhesive layer 3.

Thereafter, the holding by the vacuum chuck is released. Thereby, as shown in FIG. 1D, the thin film wafer W ₂ is fixed to the holding material 4, and the thin film wafer W ₂ is held by the holding material 4. Finally, the protective film 1 is removed as shown in FIG.

Incidentally, the holding member 4 to such a thin film wafer W ₂ is fixed, it may be fixed to the stage 5 or the like by vacuum suction as shown in Figure 5 (a). Further, when the holding material 4 is made of a magnetic material, the holding material 4 may be fixed to a stage 6, a jig, or a carrier made of an electromagnet or a magnet by a magnetic force as shown in FIG. 5B. Is possible.

The thin wafer W _2, treated with fixed state, for example, following steps in the holding member 4 is applied. FIG 6 (a) ~ FIG 6 (e) is a schematic view of a state in which subjected to processing to thin the wafer W ₂ which is fixed to the holding member 4 according to this embodiment. Here, with a thin film wafer W _2, through holes 11 penetrating from the surface side to the back side, and a thin film wafer W ₂ of the surface, back surface, an insulating film formed in the through holes 11 (not shown) I will explain what they have.

As shown in FIG. 6 (a), to fix the thin-film wafer W ₂ to the holding member 4 in the process as described above. Then, a seed layer 12 made of a metal such as Ni or the like by electroless plating on the entire surface of the thin film wafer W ₂ as shown in Figure 6 (b). Electroless plating can be performed, for example, by dipping into a plating solution or spraying from both sides in an inert atmosphere.

After forming the seed layer 12 in the thin film wafer W _2, paste the sheet-shaped resist 13 on both sides of the thin film wafer W _2, patterning of the resist 13 as shown in FIG. 6 (c). Thereafter, as shown in FIG. 6D, a wiring layer 14 made of a metal such as Cu is formed on the seed layer 12 by electrolytic plating. The wiring layer 14 is formed not only in the front and back surfaces of the thin film wafer W ₂ but also in the through holes 11.

After the wiring layer 14 is formed, the resist 13 is removed, and then the seed layer 12 under the resist 13 is removed by etching. As a result, the wiring on the front and back surfaces of the thin-film wafer W ₂ as shown in FIG. 6 (e) is formed. The wiring formed on the back surface of the thin film wafer W ₂ of the formed wire on the surface and the thin film wafer W ₂ is electrically connected by wiring formed in the through holes 11.

In the present embodiment, the adhesive layer 3 is provided along the outer periphery of the thin film wafer W ₂ on the holding member 4 having the opening 4 a, and the outer peripheral portion of the back surface of the thin film wafer W ₂ is adhered to the adhesive layer 3. since securing the wafer W ₂ to the holding member 4, it is possible to handle thin wafers W ₂ as usual thick wafer. In the present embodiment, although the adhesive layer 3 is provided on the holding member 4 side, an adhesive layer may be 3 provided on the thin film wafer W ₂ side. Even in this case, the same effect as that obtained when the adhesive layer 3 is provided on the holding material 4 side can be obtained.

Further, this configuration, in a state of fixing the thin-film wafer W ₂ to the holding member 4, it becomes possible to perform processing on the rear surface of the thin film wafer W _2. Thus, it is possible to it is possible to perform the process on both sides of the thin film wafer W ₂ at a time, reducing the number of replacement steps of the holding member 4. Therefore, the number of steps can be reduced.

Furthermore, it is possible to perform the process on both sides of the thin film wafer W ₂ at a time, it is possible to reduce the process cost. Further, since it is possible to reduce the number of replacement steps of the holding member 4, it is possible to reduce the failure probability of the thin film wafer W _2, it is possible to improve the yield.

Moreover, in this embodiment, since the holding member 4 is formed in a ring shape, not only it is possible to process by supplying a fluid to the backside of the thin film wafer W ₂ through the through hole 11, the thin film wafer the resist 13 on the rear surface of the W ₂ can be attached easily. It is also possible to pattern the resist 13 pasted to the back surface of the thin film wafer W ₂ by photolithography.

In the present embodiment, in the state where the thin film wafer W ₂ is fixed to the holding material 4, the back surface of the thin film wafer W ₂ is open, so that the processing accuracy can be improved. For example, an example of forming the wiring by electroplating both surfaces of the thin film wafer W _2, in the process of forming the wiring by such electrolytic plating, thin film wafer as shown in FIG. 14 (a) If the holding material 101 is attached to the back surface of W, since the holding material 101 exists on the back surface of the thin film wafer W, one end of the through hole 102 is closed, and the plating solution stays in the through hole 102. Resulting in. As a result, the plating 103 is preferentially performed only at the entrance of the through hole 102, and the through hole 102 is not embedded, and a large void (void) is generated in the through hole 102. Also, when the holding material 101 is peeled from the thin film wafer W, the plating 103 on the bottom surface of the through hole 102 is pulled out as shown in FIG. In contrast, in the present embodiment, since the rear surface of the thin wafer W ₂ is opened, it is possible to embed securely wiring layer 14 in the through holes 11 as shown in FIG. 7, to reduce the void be able to. In FIG. 7, reference numeral 15 denotes an insulating layer.

In the present embodiment, the length d ₁ in the direction orthogonal to the outer periphery of the thin film wafer W _{2 in} the adhesive layer 3 is larger than the length d ₂ in the thickness direction of the adhesive layer 3, so the thin film wafer W _2. The contact area can be increased, and the reliability of adhesion can be improved.

In this embodiment, since the end portion of the inner circumferential side and the thin film wafer W ₂ side of the holding member 4 is chamfered, it is possible to suppress the cracking of the thin wafer W ₂ due to stress concentration. In addition, you may form in a curved surface shape instead of chamfering this edge part, and the same effect is acquired also in this case.

In this embodiment, the surface roughness of the rear surface of the thin-film wafer W ₂ is in the fourth or less of the thickness of the adhesive layer 3, a thin film wafer W at the time of fixing the thin-film wafer W ₂ to the holding member 4 ₂ cracks can be suppressed. That is, the back surface of the thin film wafer W ₂ may be irregularities remain. On the other hand, when fixing the thin-film wafer W ₂ is the holding member 4, for pressing the thin film wafer W ₂ relative to adhesive layer, the thin thickness of the adhesive layer 3, the entire adhesive layer 3 is a thin film wafer W ₂ will enter into the recesses on the back surface. As a result, will be in contact with the back surface of the convex portion of the thin-film wafer W ₂ and the holding member 4, there is a possibility that cracking is thin wafer W _2. In contrast, in the present embodiment, the surface roughness of the rear surface of the thin-film wafer W ₂ is in the fourth or less of the thickness of the adhesive layer 3, pressing a thin wafer W ₂ with respect to the adhesive layer 3 Even in this case, the adhesive layer 3 can be present between the convex portion on the back surface of the thin film wafer W ₂ and the holding material 4. Thus, it is possible to suppress the cracking of the thin wafer W _2.

(Second Embodiment)
Hereinafter, a second embodiment will be described. In this embodiment, an example in which a reinforcing plate is bonded to the back surface of a thin film wafer will be described. FIGS. 8A and 8B are a schematic vertical sectional view and a plan view of the holding material in a state where the thin film wafer according to the present embodiment is fixed.

Reinforcing plate 21 is bonded to the rear surface of the thin film wafer W ₂ as shown in FIG. 8 (a) and 8 (b). Reinforcing plate 21 is formed substantially in the same shape as the thin-film wafer W _2. The reinforcing plate 21 has an opening 21a in a necessary portion that the rear surface of the thin-film wafer W ₂ is opened is formed when performing the process on the rear surface of the thin film wafer W _2. Through the opening 21a, the fluid chemical solution or gas or the like for performing processing to thin the wafer W ₂ is in contact with the rear surface of the thin film wafer W _2.

In this embodiment, since the reinforcing plate 21 on the rear surface of the thin film wafer W ₂ are bonded, you can use small holding material 4 width. That is, the width of the holding member 4, when correcting the warpage due to stress possessed by the film wafer W _2, the ends of the adhesive layer 3 side of the holding member 4 or the thin wafer W ₂ at the outermost periphery of the thin wafer W ₂ While stress generated should be designed to be much smaller than the breaking stress possessed by the film wafer W _2, the width of the holding member 4 is large is not preferable. In this embodiment, since the reinforcing plate 21 on the rear surface of the thin film wafer W ₂ is bonded, even when using a holding material 4 width is small, the end portion of the adhesive layer 3 side of the holding member 4 or The stress generated in the thin film wafer W _{2 at} the outermost periphery of the thin film wafer W ₂ can be sufficiently reduced with respect to the breaking stress of the thin film wafer W ₂ . Thereby, the holding | maintenance material 4 with a small width | variety can be used. Since the opening 21a is formed in the reinforcing plate 21, reinforcing plate 21 when performing the process on the rear surface of the thin film wafer W ₂ is not an obstacle.

Further, in this embodiment, the reinforcing plate 21 is used, but the same effect can be obtained even if a film formed by coating the back surface of the thin film wafer W ₂ instead of the reinforcing plate 21 is used. Can do. Here, the film, opening the necessary parts that rear surface is opened in the thin film wafer W ₂ when performing the same procedure the reinforcing plate 21 on the rear surface of the thin film wafer W ₂ is formed.

(Third embodiment)
The third embodiment will be described below. In this embodiment, an example in which a holding member formed in a disc shape is used will be described. FIG. 9A and FIG. 9B are a schematic vertical sectional view and a plan view of the holding material in a state where the thin film wafer according to the present embodiment is fixed, and FIG. 10A and FIG. b) Other schematic vertical sectional views and plan views of the holding material in a state where the thin film wafer according to the present embodiment is fixed.

As shown in FIGS. 9A to 10B, the holding member 4 is formed in a disc shape. 9A and 9B, the holding material 4 is formed with a plurality of openings 4 b communicating with the space between the thin film wafer W ₂ and the holding material 4 at a position inside the adhesive layer 3. Has been. The space between the FIG. 10 (a) and FIG. 10 from a position outside from the adhesive layer 3 on the surface of the holding member 4 in (b) to the position of the inner side of the adhesive layer, the thin film wafer W ₂ and the holding member 4 A plurality of openings 4c communicated with each other is formed. That is, the opening 4 c is formed so as to straddle the adhesive layer 3.

  In the present embodiment, since the holding material 4 is formed in a disc shape and the openings 4b and 4c are formed in the holding material 4, the same effect as in the first embodiment can be obtained. In the present embodiment, the holding material 4 is formed in a disc shape, but may not be in a disc shape. Further, when the adhesive layer 3 is provided as shown in FIG. 3, the openings 4 b and 4 c need not be formed in the holding material 4. In this case, the opening formed between the adhesive layer 3 and the adhesive layer 3 exhibits the same function as the openings 4b and 4c.

(Fourth embodiment)
Hereinafter, a fourth embodiment will be described. In this embodiment, an example will be described in which a holding material in which a step is formed between an outer peripheral portion of the holding material and a portion facing the thin film wafer of the holding material inside the outer peripheral portion is described. FIG. 11A and FIG. 11B are a schematic vertical sectional view and a plan view of the holding material in a state where the thin film wafer according to the present embodiment is fixed.

As shown in FIG. 11A and FIG. 11B, the holding material 4 has a step between the outer peripheral portion of the holding material 4 and the portion of the holding material 4 facing the thin film wafer W ₂ inside thereof. Is formed. Specifically, the position of the upper surface of the inner portion of the holding material 4 facing the thin film wafer W < _b > ₂ is lower than the upper surface of the outer peripheral portion of the holding material 4. The holding material 4 is formed with a plurality of openings 4 d communicating with the space between the thin film wafer W ₂ and the holding material 4 at a position inside the adhesive layer 3.

In this embodiment, the upper surface of the opposing inner portions to thin the wafer W ₂ of the holding member 4, the position is lower than the upper surface of the outer peripheral portion of the holding member 4, a thin film wafer W ₂ and the holding member 4 Contact can be reliably suppressed. That is, when the space between the thin film wafer W ₂ and the holding material 4 is narrow, there is a possibility that the thin film wafer W ₂ and the holding material 4 come into contact with each other due to surface tension. In contrast, in the present embodiment, the upper surface of the opposing inner portions to thin the wafer W ₂ of the holding member 4, the position is lower than the upper surface of the outer peripheral portion of the holding member 4, a thin film wafer W ₂ The space between the holding member 4 is wide and this can be suppressed.

  In this embodiment, since the opening 4d is formed, the same effect as in the first embodiment can be obtained. In this embodiment, the opening 4d is formed in the holding material 4. However, when the adhesive layer 3 is provided as shown in FIG. 3, the opening 4d is not formed in the holding material 4. Also good. Moreover, you may form the opening 4d so that the adhesive layer 3 may be straddled similarly to the opening 4c shown by Fig.10 (a) and FIG.10 (b).

(Fifth embodiment)
Hereinafter, a fifth embodiment will be described. In this embodiment, an example in which a balloon is inflated to flatten a thin film wafer will be described. FIG. 12A to FIG. 12D are schematic views of the thin film wafer holding process according to the present embodiment.

In the first embodiment, after the wafer W ₁ is thinned, the holding material 4 is attached to the thin film wafer W ₂ without releasing the suction by the vacuum chuck. However, due to the configuration of the apparatus, the thin film of the wafer W ₁ is used. The forming step and the thin film wafer W ₂ holding step may be performed at different locations. In this case, when releasing the suction by the vacuum chucks, the thin film wafer W ₂ is to lead to a bent by the internal stress. At this time, when being placed on the stage 31 for holding the holding member 4, the thin film wafer W ₂ as shown in FIG. 12 (a) is in the state is curved. In this state, if the thin film wafer W ₂ is forcibly flattened, there is a high possibility that the thin film wafer W ₂ is locally stressed and damaged.

For this reason, by disposing a thin film wafer W ₂ of the center or thin wafers W balloon 32 made of an elastic body to the center of curvature of _2, as shown in FIG. 12 (b), along a curved portion However, the balloon 32 is inflated as shown in FIG. Finally, as shown in FIG. 12D, the balloon 32 is inflated until the outer peripheral portion of the thin film wafer W ₂ comes into contact with the stage 31 through the protective film 1 to flatten the thin film wafer W _2. . Thereafter, by the same step as that shown in FIG. 1 (c) ~ FIG 1 (e), attaching the thin wafer W ₂ to the holding member 4.

In this embodiment, the center of the thin wafer W _2, or by placing a balloon 32 made of an elastic body in the center of the curved portion of the thin-film wafer W _2, inflating the balloon 32, to correct the warpage of the thin film wafer W ₂ Therefore, the thin film wafer W ₂ can be flattened while suppressing cracking of the thin film wafer W ₂ .

(Sixth embodiment)
Hereinafter, a sixth embodiment will be described. In this embodiment, an example in which a cooled holding material is fixed to a thin film wafer will be described. FIGS. 13A to 13D are schematic views of the thin film wafer holding step according to the present embodiment.

As shown in FIG. 13 (a), a thin film wafer W ₂ is attached to the holding member 42 on the rear surface of the thin film wafer W ₂ through the ring-shaped contact layer 41 in the state and at room temperature in the state adsorbed on the stage 2 . The holding material 42 has substantially the same structure as the holding material 4, but the contact layer 41 and the holding material 42 are formed with vacuum holes 41 a and 42 a, respectively. The thin film wafer W <b> ₂ is attached to the holding material 42 via the contact layer 41 by performing vacuuming through these holes 41 a and 42 a.

Then, to release the retention of the thin film wafer W ₂ by the vacuum chuck stage 2. Thus, the thin film wafer W ₂ is vacuum-sucked to the holding member 42, the thin film wafer W ₂ as shown in FIG. 13 (b) is held by the holding member 42. Thereafter, the protective film 1 is removed.

Subsequently, as shown in FIG. 13C, in this state, the surface of the thin film wafer W ₂ is maintained at a temperature lower than room temperature or process temperature, for example, −50 ° C. via the ring-shaped contact layer 43. The held holding material 44 is attached. The contact layer 43 and the holding material 44 have the same structure as the contact layer 43 and the holding material 44. In other words, the contact layer 43 and the holding member 44, the hole 43a for evacuation, respectively, are 44a is formed, by performing evacuation through the holes 43a, 44a, the thin film wafer _{W 2} is holding material 44 is attached via a contact layer 43.

The contact layers 41 and 43 are made of a material that can be sufficiently elastically deformed at a cooling temperature, room temperature, or process temperature. Examples of such a material include rubber materials and other resin materials. In the contact layers 41 and 43, the length of the contact layers 41 and 43 in the direction orthogonal to the outer periphery of the thin film wafer W ₂ is larger than the length of the contact layers 41 and 43 in the thickness direction.

After installing the thin-film wafer W ₂ to the holding member 44, in this state, returning the temperature of the holding member 44 to the room temperature or process temperature. Thereafter, as shown in FIG. 13 (d), the holding members 42 and 44 are held by a ring-shaped fixing member 45 using mechanical or magnetic force. In FIG. 13D, the left diagram is an example in which the holding members 42 and 44 are mechanically sandwiched, and the right diagram illustrates an example in which the retaining members 42 and 44 are sandwiched using magnetic force. .

In this embodiment, mounting the thin film wafer W ₂ to lower the holding member 44 as compared with the room temperature or the like temperature, since returned to room like the temperature of the holding member 44 in this state, the contact layer 43 by the expansion of the holding member 44 uniformly tensile stress in the thin film wafer W ₂ via can provide. Thus, it is possible to reduce warping due to the film stress and dead weight of the thin film wafer W _2.

In the case where the holding member 44 is composed of Si can provide a tensile stress in the thin film wafer W ₂ at any temperature. Also in the case where the linear expansion coefficient of the formation of the holding member 44 from Si greater material tensile stress applied to the thin film wafer W ₂ as the temperature rise increases. Here, when the tensile stress is too large, it may crack resulting in progression from chipping of the thin-film wafer W ₂ circumference. Then, the tensile stress applied to the thin film wafer W ₂ with an increase in temperature if the linear expansion coefficient conversely to form a holding member 44 from the Si less material is reduced. Here, if the tensile stress is too small, the warpage of the thin film wafer W ₂ can be reduced, but the flat thin film wafer W ₂ cannot be obtained. For this reason, the constituent material of the holding member 44 and the temperature of the holding member 44 having the optimum linear expansion coefficient should be selected from the process temperature requirements.

In the present embodiment, the contact layer 43 is used, but the same effect can be obtained even when the adhesive layer 3 is used instead of the contact layer 43. The temperature of the holding member 42 for attaching the holding member 42 a thin film wafer W ₂ in this embodiment is has a room temperature, and maintained at a low temperature in comparison with similarly room temperature or process temperature and the holding member 44 advance, it may be attached to a thin film wafer W ₂ in this state.

The present invention is not limited to the description of the above embodiment, and the structure, material, arrangement of each member, and the like can be appropriately changed without departing from the gist of the present invention. For example, in the above embodiment, the thin film wafer W ₂ made of Si is used for explanation. However, it is obvious that the present invention can be applied to a compound semiconductor substrate such as SOI, GaAs, etc. It is effective not only for the thin film material holding method.

(A)-(e) is a schematic diagram of the wafer thin film formation process and thin film wafer holding process which concern on 1st Embodiment. It is a typical top view of the holding material in the state where the thin film wafer concerning a 1st embodiment was fixed. It is a typical top view of the holding material in the state where the thin film wafer concerning a 1st embodiment was fixed. It is an enlarged view of the edge part vicinity of the contact bonding layer side of the holding material which concerns on 1st Embodiment. (A) And (b) is a schematic diagram of the state which fixed the holding material to which the thin film wafer which concerns on 1st this Embodiment was fixed to the stage. (A)-(e) is a schematic diagram of the state which has processed the thin film wafer fixed to the holding material which concerns on 1st Embodiment. 1 is a schematic vertical sectional view of a thin film wafer according to a first embodiment. (A) And (b) is the typical vertical sectional view and top view of the holding material of the state to which the thin film wafer which concerns on 2nd Embodiment was fixed. (A) And (b) is the typical vertical sectional view and top view of a holding material in the state where the thin film wafer concerning a 3rd embodiment was fixed. (A) And (b) is the other typical vertical sectional view and top view of the holding material of the state to which the thin film wafer which concerns on 3rd Embodiment was fixed. (A) And (b) is the typical vertical sectional view and top view of the holding material of the state to which the thin film wafer concerning 4th Embodiment was fixed. (A)-(d) is a schematic diagram of the thin film wafer holding process which concerns on 5th Embodiment. (A)-(d) is a schematic diagram of the thin film wafer holding process which concerns on 6th Embodiment. (A) is the schematic diagram which showed the state which embed | plated metal in the through-hole of the conventional thin film wafer, (b) embed | plated metal in the through-hole of the conventional thin film wafer, and then from the wafer It is the schematic diagram which showed the state when peeling a holding material.

Explanation of symbols

W ₁ ... wafer, W ₂ ... thin film wafer, 3 ... adhesive layer, 4, 42, 44 ... holding material, 4a to 4d ... opening, 32 ... balloon.

Claims (5)

A holding material and a thin film substrate are bonded to each other with an adhesive layer provided along the outer periphery of the thin film substrate, and the thin film substrate is fixed to the holding material.
At least one of the holding material and the adhesive layer has an opening communicating with a space between the thin film substrate and the holding material.   2. The thin film according to claim 1, wherein the holding material is formed in a ring shape, and an end portion on an inner peripheral side of the holding material and the thin film substrate side is chamfered or formed in a curved shape. A method for holding a substrate.   3. The method for holding a thin film substrate according to claim 1, wherein a length of the adhesive layer in a direction orthogonal to an outer periphery of the thin film substrate is larger than a length of the adhesive layer in a thickness direction. Contacting a thin film substrate with a balloon made of an elastic body, inflating the balloon, and correcting the warp of the thin film substrate;
A method of holding the thin film substrate, comprising: fixing the thin film substrate with the warp corrected to a holding material with an adhesive layer interposed therebetween. Fixing the thin film substrate to the holding material by the thin film substrate holding method according to any one of claims 1 to 4,
And a step of processing the front surface and the back surface of the thin film substrate fixed to the holding material.

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