Infrared laser assisted mechanical de-bonding method

Abstract

The invention provides an infrared laser assisted mechanical de-bonding method, which comprises the following steps of: performing laser de-bonding on all or part of the periphery of the edge of a laminated body by adopting infrared laser to obtain an edge differentiated laminated body; performing mechanical de-bonding on the edge differentiation laminated body to complete separation of the wafer and the wafer substrate; the laminated body is obtained by bonding the wafer and the wafer substrate through an infrared effect adhesive. According to the method, infrared laser de-bonding and mechanical de-bonding are combined for use, so that the wafer and the wafer substrate are completely separated, and the wafer de-bonding efficiency is greatly improved on the basis of ensuring that the core function area of the wafer is not damaged.

Description

Technical Field

[0001] This invention belongs to the field of wafer processing technology and relates to a method for infrared laser-assisted mechanical debonding. Background Technology

[0002] Currently, HBM has broken through the "memory wall," achieving high bandwidth and high capacity, becoming the most powerful auxiliary technology for AI chips. HBM mainly uses TSV technology and 3D stacking technology, which greatly improves data processing speed. However, while improving performance, it also places stringent requirements on chip thickness, making wafer thinning technology (such as TSV through-silicon via process) a key step. The thinned wafer (usually less than 100μm thick) needs to be fixed to the support substrate using temporary bonding technology for processing. After processing, the support substrate needs to be peeled off. To achieve this, temporary bonding and debonding (TBDB) technology is required.

[0003] Generally, existing temporary bonding and debonding technologies involve the use of an adhesive layer, which is placed directly between the wafer and the wafer substrate. After the back-side processing of the wafer is completed, the wafer and wafer substrate can be separated using various debonding techniques (such as laser debonding, mechanical debonding, or thermal slip debonding). Because HBM chips are thermally sensitive to laser agents, using a full-area surface-scan laser lift-off method can cause laser damage to the chip, affecting the yield. Therefore, current temporary debonding solutions for HBM stacking mainly employ mechanical blade separation of the wafer edge adhesive layer followed by mechanical separation. However, this method has the following problems: 1. Stress damage risk: The mechanical stress generated during blade dicing can easily cause ultra-thin wafers (thickness <30μm) to crack; 2. Poor process compatibility: Blade dicing has extremely stringent requirements for machine precision, making it almost impractical for ultra-thin wafers (e.g., thickness <20μm); 3. Contamination risk: Blade contact may introduce and carry out the adhesive layer, contaminating the blade and affecting subsequent debonding. Existing laser peeling technology (such as patent CN 113166624 B) achieves peeling by thermally decomposing the adhesive layer through infrared laser irradiation, but it requires full-area scanning, which is inefficient and can easily cause laser damage to the chip.

[0004] Therefore, there is an urgent need to explore a new wafer debonding process to reduce damage to the functional areas of the wafer and improve the yield of finished wafers. Summary of the Invention

[0005] To address the technical problems existing in the prior art, this invention provides an infrared laser-assisted mechanical debonding method. This method combines infrared laser debonding with mechanical debonding to achieve complete separation of the wafer from the wafer substrate while ensuring no damage to the core functional areas of the wafer, thereby greatly improving the wafer debonding efficiency.

[0006] To achieve the above-mentioned technical effects, the present invention adopts the following technical solution:

[0007] This invention provides a method for infrared laser-assisted mechanical debonding, the method comprising:

[0008] Infrared lasers are used to perform laser debonding on all or part of the circumferential edge of the laminate to obtain an edge-differentiated laminate.

[0009] Mechanical debonding is performed on the edge-differentiated stack to complete the separation of the wafer from the wafer substrate;

[0010] The laminate is formed by bonding the wafer and the wafer substrate together using an infrared-effect adhesive.

[0011] As a preferred technical solution of the present invention, the wavelength of the infrared laser is 2.5~25μm, and the power of the infrared laser is 30~70 W.

[0012] As a preferred embodiment of the present invention, the scanning width of the infrared laser does not exceed the effective unit of the wafer.

[0013] Preferably, the scanning angle of the infrared laser is 1~360°.

[0014] Preferably, the scanning rate of the infrared laser is 50~1000 mm / s.

[0015] As a preferred technical solution of the present invention, the method for mechanical debonding includes:

[0016] Fix the wafer and wafer substrate, apply a pulling force to the wafer and / or wafer substrate, and lift the wafer substrate at a constant speed until the wafer and wafer substrate are completely separated.

[0017] As a preferred technical solution of the present invention, the tensile force applied by mechanical debonding is 20~60N.

[0018] Preferably, the wafer substrate has a rise rate of 0.1~0.5 mm / s.

[0019] As a preferred technical solution of the present invention, vibration is used to apply shear force to assist in debonding during the mechanical debonding process.

[0020] As a preferred technical solution of the present invention, the wafer substrate is an infrared-transparent material.

[0021] As a preferred technical solution of the present invention, the components of the infrared effect adhesive include a main resin, a catalyst, an inhibitor, and a solvent.

[0022] As a preferred embodiment of the present invention, the main resin includes vinyl-containing polysiloxane and hydrogen-containing polysiloxane.

[0023] Preferably, the viscosity of the vinyl polysiloxane is 100~2000 mPa·s.

[0024] Preferably, the content of hydrogen-containing polysiloxane Si-H groups is 0.1~1.5 mol%.

[0025] Preferably, the molar ratio of Si-H groups to vinyl groups in the main resin is (0.5~2):1.

[0026] As a preferred embodiment of the present invention, the infrared effect adhesive further includes an infrared laser response-enhancing resin.

[0027] Preferably, the infrared laser response-enhancing resin includes epoxy-modified polysiloxane, wherein the epoxy equivalent of the epoxy-modified polysiloxane is 200~1000 g / eq.

[0028] Preferably, the content of infrared laser response-enhancing resin in the infrared effect adhesive is 0~20 wt%.

[0029] Compared with the prior art, the present invention has at least the following beneficial effects:

[0030] (1) This invention provides a method for infrared laser-assisted mechanical debonding. This method combines infrared laser debonding with mechanical debonding to achieve complete separation of the wafer from the wafer substrate. At the same time, it can not only avoid damage to the core functional areas of the wafer by the laser, but also avoid damage to the wafer structure by mechanical debonding.

[0031] (2) The present invention provides an infrared laser-assisted mechanical debonding method, which greatly improves wafer debonding efficiency and significantly improves finished product yield.

[0032] (3) The present invention provides an infrared laser-assisted mechanical debonding method, which is suitable for the separation of wafers with a thickness of less than 30 μm without causing cracking.

[0033] (4) The present invention provides an infrared laser-assisted mechanical debonding method, which is applicable not only to the preparation of ultrathin HBM, but also to ultrathin OLED flexible films, etc. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of the laminate in the infrared laser-assisted mechanical debonding method provided by the present invention;

[0035] Figure 2 This is a schematic diagram of the scanning area for infrared laser debonding in the infrared laser-assisted mechanical debonding method provided by the present invention.

[0036] Figure 3 This is a schematic diagram illustrating the separation of mechanical debonding in the infrared laser-assisted mechanical debonding method provided by the present invention.

[0037] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0038] The technical solution of this application will be further described below through specific implementation methods.

[0039] This invention provides a method for infrared laser-assisted mechanical debonding, the method comprising:

[0040] Infrared lasers are used to perform laser debonding on all or part of the circumferential edge of the laminate to obtain an edge-differentiated laminate.

[0041] Mechanical debonding is performed on the edge-differentiated stack to complete the separation of the wafer from the wafer substrate;

[0042] The laminate is formed by bonding the wafer and the wafer substrate together using an infrared-effect adhesive.

[0043] In this invention, a wafer and a wafer substrate are bonded together using an infrared-effect adhesive to form a laminate. After the required processing, an infrared laser is first used to partially or completely debond the laminate circumferentially, causing circumferential differentiation and reducing the adhesive force between the wafer and the wafer substrate. Then, mechanical debonding is used to achieve complete separation of the wafer and the wafer substrate. On the one hand, the infrared laser scans the circumferential region of the laminate, avoiding damage to the functional areas of the wafer. On the other hand, it also reduces the magnitude of the separation force applied during subsequent mechanical debonding, lowering the difficulty of mechanical debonding and improving separation efficiency. Simultaneously, it avoids damage to the wafer structure during mechanical debonding, significantly improving the yield of the finished product.

[0044] In one specific embodiment of the present invention, the wavelength of the infrared laser is 2.5~25μm, and the power of the infrared laser is 30~70 W. The wavelength can be 2.5μm, 5μm, 7.5μm, 10μm, 15μm, 20μm, or 25μm, etc., and the power can be 30W, 35W, 40W, 45W, 50W, 55W, 60W, 65W, or 70W, etc., but is not limited to the listed values; other unlisted values ​​within the above ranges are also applicable.

[0045] In one specific embodiment of the present invention, the scanning width of the infrared laser does not exceed the effective cell of the wafer.

[0046] In one specific embodiment of the present invention, the scanning width refers to the farthest distance the infrared laser scan extends from the wafer edge into the wafer interior. It can be adjusted based on the actual distance from the edge of the wafer's functional area to the wafer edge, and the degree of separation of the laminate edges after laser scanning; no further limitation is made here. For example, the infrared laser scanning depth can be 1~5 mm.

[0047] In one specific embodiment of the present invention, the scanning angle of the infrared laser is 1~360°, such as 1°, 15°, 30°, 45°, 60°, 75°, 90°, 120°, 150°, 180° or 360°, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0048] In one specific embodiment of the present invention, the scanning angle of the infrared laser can be adjusted according to the degree of separation at the edge of the laminate. For example, for laminates with low adhesion between the wafer and the substrate, a single scan of 10-15° can be performed in a circumferential region, with intervals between scans. The scan length is 50%-75% of the total length of the laminate edge, which is sufficient to meet the requirements of subsequent mechanical debonding. As another example, for laminates with high adhesion between the wafer and the substrate, multiple or single scans can be used to completely cover the length of the laminate edge to meet the requirements of subsequent mechanical debonding.

[0049] In one specific embodiment of the present invention, the scanning rate of the infrared laser is 50~1000 mm / s, such as 50 mm / s, 100 mm / s, 150 mm / s, 200 mm / s, 250 mm / s, 300 mm / s, 400 mm / s, 500 mm / s, 600 mm / s, 700 mm / s, 800 mm / s, 900 mm / s or 1000 mm / s, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0050] In one specific embodiment of the present invention, the mechanical debonding method includes: fixing the wafer and the wafer substrate, applying a pulling force to the wafer and / or the wafer substrate, and uniformly lifting the wafer substrate until the wafer and the wafer substrate are completely separated.

[0051] In one specific embodiment of the present invention, the wafer and the wafer substrate can be fixed by suction cups in the mechanical debonding device, with a suction uniformity of ±2%.

[0052] In one specific embodiment of the present invention, the tensile force can be applied perpendicular to the wafer, and can be applied alone to the wafer or the wafer substrate, or together to the wafer and the wafer substrate. The tensile force is 20~60 N, such as 20 N, 25 N, 30 N, 35 N, 40 N, 45 N, 50 N, 55 N or 60 N, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0053] In one specific embodiment of the present invention, the lifting rate of the wafer substrate is 0.1~0.5 mm / s, such as 0.1 mm / s, 0.2 mm / s, 0.3 mm / s, 0.4 mm / s, or 0.5 mm / s, etc., and is not limited to the listed values; other unlisted values ​​within this range are also applicable. Under the pulling force, the wafer and the wafer substrate separate at a uniform speed, avoiding wafer damage caused by excessively fast separation speed.

[0054] In one specific embodiment of the present invention, vibration is used to apply shear force during the mechanical debonding process to assist debonding. The vibration frequency can be 10~100 Hz, and the vibration generates a shear force parallel to the wafer to assist debonding.

[0055] In one specific embodiment of the present invention, the wafer substrate is an infrared-transmitting material, such as SiC, ZnSe, GaAs, or Si, preferably monocrystalline silicon.

[0056] In one specific embodiment of the present invention, the components of the infrared effect adhesive include a host resin, a catalyst, an inhibitor, and a solvent.

[0057] In one specific embodiment of the present invention, the main resin contains Si-O or other infrared-sensitive chemical bonds, which can achieve infrared mechanical debonding.

[0058] In one specific embodiment of the present invention, the main resin includes vinyl-containing polysiloxane and hydrogen-containing polysiloxane.

[0059] In one specific embodiment of the present invention, the vinyl-containing polysiloxane includes Wacker HDK® RH-Vi1321, RH-Vi1322 or RH-Vi1360, etc.

[0060] In one specific embodiment of the present invention, the hydrogen-containing polysiloxane includes Runhe RH-H502, Dow Corning MHX-1107, Chenxi CX-351H or CX-350D, etc.

[0061] In one specific embodiment of the present invention, the viscosity of the vinyl polysiloxane is 100~2000 mPa·s, such as 100 mPa·s, 200 mPa·s, 500 mPa·s, 800 mPa·s, 1000 mPa·s, 1200 mPa·s, 1500 mPa·s, 1800 mPa·s or 2000 mPa·s, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0062] In one specific embodiment of the present invention, the Si-H group content of the hydrogen-containing polysiloxane is 0.1~1.5 mol%, such as 0.1 mol%, 0.2 mol%, 0.5 mol%, 0.8 mol%, 1.0 mol%, 1.2 mol%, or 1.5 mol%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0063] In one specific embodiment of the present invention, the molar ratio of Si-H groups to vinyl groups in the main resin is (0.5~2):1, such as 0.5:1, 0.8:1, 1:1, 1.2:1, 1.5:1, 1.8:1, or 2:1, but not limited to the listed values; other unlisted values ​​within this range are also applicable. Meeting the above-mentioned molar ratio of Si-H groups to vinyl groups in the main resin ensures curing strength and prevents wafer-substrate separation during processing. If the molar ratio of Si-H groups to vinyl groups is less than 0.5, the crosslinking density is too low to allow the adhesive to cure. If the molar ratio of Si-H groups to vinyl groups exceeds 2, the crosslinking density is too high to obtain adequate adhesive force, making subsequent mechanical separation difficult and affecting product yield.

[0064] In one specific embodiment of the present invention, the catalyst can be a platinum catalyst, including an isopropanol / ethanol solution of chloroplatinic acid (H2PtCl6·6H2O), a platinum(O)-divinyltetramethyldisiloxane complex, a complex of chloroplatinic acid with tetramethyltetravinylcyclotetrasiloxane (such as D4Vi), or platinum with a phenyl / alkynyl ligand, etc., preferably a platinum(O)-divinyltetramethyldisiloxane complex. The addition of the catalyst can control the curing speed and ensure the stability of the product.

[0065] In one specific embodiment of the present invention, the amount of catalyst added can be 0.5~50 ppm.

[0066] In one specific embodiment of the present invention, the inhibitor includes any one or a combination of at least two of 3-methyl-1-pentyn-3-ol, tetramethyltetravinylcyclotetrasiloxane, ethynylcyclohexanol, tetramethylethylenediamine, tetramethylbutynol, methylbutynol, diallyl maleate, or 2-methyl-3-butyn-2-ol.

[0067] In one specific embodiment of the present invention, the amount of inhibitor added is 0.1~0.5%. The role of the inhibitor is to inhibit the cross-linking and curing of Si-H groups and vinyl groups in the adhesive, so as to avoid the adhesive solution becoming cloudy or gelling before coating and heating curing, which would result in poor coating uniformity and reduced film strength.

[0068] In one specific embodiment of the present invention, the solvent includes aliphatic hydrocarbons, aromatic hydrocarbons, ketones, etc., but is not limited thereto. More specifically, examples include any one or a combination of at least two of the following: ethylcyclohexane, p-menthane, limonene, mesitylene, cumene, MIBK (methyl isobutyl ketone), cyclopentanone, cyclohexanone, 1,4-dioxane, etc.

[0069] In one specific embodiment of the present invention, the infrared effect adhesive further includes an infrared laser response enhancement resin to improve the infrared absorption rate of the edge region.

[0070] In one specific embodiment of the present invention, the infrared laser response enhancement resin includes an epoxy-modified polysiloxane, wherein the epoxy equivalent of the epoxy-modified polysiloxane is 200~1000 g / eq, such as 200 g / eq, 300 g / eq, 400 g / eq, 500 g / eq, 600 g / eq, 700 g / eq, 800 g / eq, 900 g / eq, or 1000 g / eq, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0071] In one specific embodiment of the present invention, the content of infrared laser response-enhancing resin in the infrared effect adhesive is 0~20 wt%, such as 1 wt%, 2 wt%, 5 wt%, 8 wt%, 10 wt%, 12 wt%, 15 wt%, 18 wt% or 20 wt%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0072] In one specific embodiment of the present invention, the laminate can be prepared using a preparation method known in the field of wafer fabrication, and is not specifically limited herein.

[0073] In one specific embodiment of the present invention, the laminate may include multiple layers, such as 2 to 3 adhesive layers, wherein at least one layer is an infrared-effect adhesive, and the remaining layers may be prepared using commonly used adhesives prepared from the laminate.

[0074] In one specific embodiment of the present invention, the method for preparing the laminate, as exemplified, includes:

[0075] Place the wafer or wafer substrate on a spin coater, turn on the vacuum system, fix the wafer or wafer substrate with a suction cup, and evenly pour 10~50ml of infrared effect adhesive onto the wafer or wafer substrate for spin coating.

[0076] Turn off the vacuum chuck, remove the wafer or wafer substrate coated with infrared effect adhesive, and bake it.

[0077] After baking, the coated surfaces of the wafer and the substrate are joined together. The wafer is then bonded in a bonding device by vacuuming, heating, and pressurizing. After cooling to room temperature, the temporary bonding of the wafer is completed.

[0078] In one specific embodiment of the present invention, the parameters in the preparation method of the laminate can be adjusted according to the bonding situation, and are not specifically limited here.

[0079] In one specific embodiment of the present invention, the spin coating rate can be set to 400~2000 rpm / 100~250 sec, preferably 800~1200 rpm / 100~150 sec. It can be adjusted according to the coating conditions of the infrared effect adhesive and is not limited to the above conditions.

[0080] In one specific embodiment of the present invention, the baking temperature can be 60~90℃, and the time can be 4~8 minutes, preferably 5 minutes. These conditions can be adjusted according to the composition of the infrared effect adhesive and are not limited to the above-mentioned conditions.

[0081] In one specific embodiment of the present invention, after the coated surfaces of the wafer and the substrate are joined together, the bonding equipment is subjected to a vacuum of ≤10 Pa, heated to 120~220℃, and pressurized at 0.1~0.5 KN for 5-10 minutes, preferably 10 minutes. These conditions can be adjusted according to the curing status of the infrared-effect adhesive and are not limited to the above conditions.

[0082] In one specific embodiment of the present invention, key process verification is performed on the laminate. Key process verification includes thinning, plasma-enhanced chemical vapor deposition (PECVD), and heat treatment.

[0083] In one specific embodiment of the present invention, during the verification of key process technology, the thinning process can be carried out by mechanical grinding and chemical thinning to reduce the wafer to 20~100μm.

[0084] In one specific embodiment of the present invention, during the verification of key process technology, PECVD can be performed by depositing 1-2 μm SiN and 2-5 μm SiO2 at 150-180 °C.

[0085] In one specific embodiment of the present invention, during the verification of key process procedures, the heating treatment can be carried out at 250°C, baked in an N2 atmosphere for 2 hours and then cooled to room temperature, and then heated to 250°C, and the cycle can be repeated 4 times.

[0086] In one specific embodiment of the present invention, after the key process verification, ultrasonic scanning is used to determine that the edges of the laminate are undamaged and the whole is free of defects such as bubbles and delamination.

[0087] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0088] Example 1

[0089] This embodiment provides a method for infrared laser-assisted mechanical debonding, the method comprising:

[0090] Layer preparation: (a) Place a 12-inch single-crystal silicon wafer and a wafer substrate (silicon) on a spin coater, turn on the vacuum system, fix the wafer with a suction cup, pour infrared effect adhesive evenly onto the wafer, turn on spin coating, set the spin coating rate to 800 rpm / 150 sec, and the film thickness to 30 μm.

[0091] (b) Turn off the vacuum chuck, remove the wafer and wafer substrate coated with infrared effect adhesive, and bake them in an 80°C oven for 5 minutes;

[0092] (c) After baking, the coated surface of the wafer and the coated surface of the wafer substrate are aligned. The wafer is then vacuumed to ≤10Pa, heated to 180℃, and pressurized to 0.2kN in a bonding equipment for 10 minutes. After cooling to room temperature, the temporary bonding of the wafer is completed.

[0093] The components of the infrared effect adhesive include: 10g of vinyl MQ resin (HDK® H20), 7g of hydrogen-containing silicone oil (RH-H502), 1.5g of X-22-343 epoxy modified silicone oil, 10 ppm of platinum (0)-divinyltetramethyldisiloxane complex, 0.1g of inhibitor, and 40g of ethylcyclohexane.

[0094] The laminate was thinned to 20 μm by grinding and then subjected to infrared laser-assisted mechanical debonding.

[0095] Infrared laser was used to perform laser debonding on all or part of the circumferential edge of the laminate. The infrared laser wavelength was 10.6 μm, the power was 30 W, the scanning speed was 100 mm / s, the scanning width was 3 mm, and the scanning angle was 360° to obtain the edge-differentiated laminate.

[0096] The edge-separated stack is placed in a mechanical debonding device. The wafer and wafer substrate are fixed by a chuck, and a pulling force of 30 N perpendicular to the wafer substrate is applied. The wafer substrate is lifted at a rate of 0.2 mm / s, thus completing the separation of the wafer and wafer substrate.

[0097] Example 2

[0098] This embodiment provides a method for infrared laser-assisted mechanical debonding, which is the same as that in Embodiment 1 except that the infrared laser wavelength is 9.2 μm.

[0099] Example 3

[0100] This embodiment provides a method for infrared laser-assisted mechanical debonding, which is the same as that in Embodiment 1 except that the infrared laser wavelength is 10.8 μm.

[0101] Example 4

[0102] This embodiment provides a method for infrared laser-assisted mechanical debonding, which is the same as that in Embodiment 1 except that the infrared laser power is 50 W.

[0103] Example 5

[0104] This embodiment provides a method for infrared laser-assisted mechanical debonding, which is the same as that in Embodiment 1 except that the infrared laser power is 70 W.

[0105] Example 6

[0106] This embodiment provides a method for infrared laser-assisted mechanical debonding, which is the same as that in Embodiment 1 except that the infrared laser scanning rate is 50 mm / s.

[0107] Example 7

[0108] This embodiment provides a method for infrared laser-assisted mechanical debonding, which is the same as that in Embodiment 1 except that the infrared laser scanning rate is 200 mm / s.

[0109] Example 8

[0110] This embodiment provides a method for infrared laser-assisted mechanical debonding, the method comprising:

[0111] The laminate prepared in Example 1 was thinned to 20 μm by grinding and then subjected to infrared laser-assisted mechanical debonding.

[0112] Infrared laser was used to perform laser debonding on all or part of the circumferential edge of the laminate. The infrared laser wavelength was 2.5 μm, the power was 50 W, the scanning speed was 150 mm / s, the scanning width was 1 mm, and the scanning angle was 180° to obtain the edge-differentiated laminate.

[0113] The edge-separated stack is placed in a mechanical debonding device. The wafer and wafer substrate are fixed by a chuck, and a pulling force of 40 N perpendicular to the wafer substrate is applied. The wafer substrate is lifted at a rate of 0.5 mm / s, thus completing the separation of the wafer and wafer substrate.

[0114] Example 9

[0115] This embodiment provides a method for infrared laser-assisted mechanical debonding, the method comprising:

[0116] The laminate prepared in Example 1 was thinned to 20 μm by grinding and then subjected to infrared laser-assisted mechanical debonding.

[0117] Infrared laser was used to perform laser debonding on all or part of the circumferential edge of the laminate. The infrared laser wavelength was 25 μm, the power was 70 W, the scanning speed was 1000 mm / s, the scanning width was 5 mm, and the scanning angle was 180° to obtain the edge-differentiated laminate.

[0118] The edge-separated stack is placed in a mechanical debonding device. The wafer and wafer substrate are fixed by a chuck, and a pulling force of 20 N perpendicular to the wafer substrate is applied. The wafer substrate is lifted at a rate of 0.1 mm / s, thus completing the separation of the wafer and wafer substrate.

[0119] Example 10

[0120] This embodiment provides a method for infrared laser-assisted mechanical debonding, wherein the infrared effect adhesive used in the preparation of the laminate does not contain X-22-343 epoxy-modified silicone oil, and all other conditions are the same as in Example 1.

[0121] Example 11

[0122] This embodiment provides a method for infrared laser-assisted mechanical debonding, wherein 1.0 g of X-22-343 epoxy-modified silicone oil is added to the infrared effect adhesive during the preparation of the laminate, and the other conditions are the same as in Example 1.

[0123] Example 12

[0124] This embodiment provides a method for infrared laser-assisted mechanical debonding, wherein 2.0 g of X-22-343 epoxy-modified silicone oil is added to the infrared effect adhesive during the preparation of the laminate, and the other conditions are the same as in Example 1.

[0125] Comparative Example 1

[0126] In this comparative example, the laminate prepared in Example 1 was used, and only infrared debonding was employed. That is, infrared laser was used to perform laser debonding on all bonding areas of the laminate. The infrared laser wavelength was 10.6 μm, the power was 30 W, the scanning speed was 100 mm / s, the scanning width was 3 mm, and the scanning angle was 360°, which completed the complete separation of the wafer and the wafer substrate.

[0127] Comparative Example 2

[0128] In this comparative example, the laminate prepared in Example 1 was used, and mechanical debonding was employed only. That is, the laminate was placed in a mechanical debonding device, the wafer and the wafer substrate were fixed by a chuck, a pulling force of 70 N perpendicular to the wafer substrate was applied, and the wafer substrate lifting rate was 0.5 mm / s, thus completing the complete separation of the wafer and the wafer substrate.

[0129] The methods provided in Examples 1-12 and Comparative Examples 1 and 2 were used to perform 100 cycles of laminate preparation-thinning-debonding. The appearance of the debonded wafers was inspected using an optical microscope, and the pass rate was calculated. The results are shown in Table 1.

[0130] Table 1

[0131]

[0132] As can be seen from the test results in Table 1, the infrared laser wavelength used in Example 2 is shorter than that in Example 1, while the infrared laser wavelength used in Example 3 is longer than that in Example 1. Since the shorter the wavelength of the infrared laser, the higher the energy, the higher the degree of debonding of the infrared laser in Example 2. Therefore, the wafer processing qualification rate of Example 2 is higher than that of Example 1, while the wafer processing qualification rate of Example 3 is lower than that of Example 1.

[0133] The infrared laser power in Examples 4 and 5 gradually increases compared to the infrared laser power used in Example 1, resulting in higher infrared laser energy per unit time. Therefore, compared to Example 1, Example 5 has the highest wafer processing pass rate, while Examples 4 and 1 show a decreasing rate in that order.

[0134] Compared with Example 1, in Examples 6 and 7, the higher the infrared laser scanning rate, the lower the debonding effect. Therefore, Example 6 has the lowest scanning rate and the highest wafer processing pass rate. The wafer processing pass rates of Examples 1 and 7 decrease in that order.

[0135] Compared with Example 1, Example 10 did not include X-22-343 epoxy-modified silicone oil, and the amount of X-22-343 epoxy-modified silicone oil added in Example 11 was less than that in Example 1. This resulted in a decrease in the infrared laser debonding effect of both examples. Therefore, the wafer processing yield of Examples 10 and 11 was lower than that of Example 1. However, the amount of X-22-343 epoxy-modified silicone oil added in Example 12 was greater than that in Example 1, so the wafer processing yield was higher than that of Example 1.

[0136] Comparative Example 1 used only infrared laser debonding, while Comparative Example 2 used only mechanical debonding; both had low wafer processing yields.

[0137] The applicant declares that the detailed structural features of the present invention are illustrated through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the components selected in the present invention, additions of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0138] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0139] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0140] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for infrared laser-assisted mechanical debonding, characterized in that, The method includes: Infrared lasers are used to perform laser debonding on all or part of the circumferential edge of the laminate to obtain an edge-differentiated laminate. Mechanical debonding is performed on the edge-differentiated stack to complete the separation of the wafer from the wafer substrate; The laminate is formed by bonding the wafer and the wafer substrate together using an infrared-effect adhesive.

2. The method for infrared laser-assisted mechanical debonding according to claim 1, characterized in that, The infrared laser has a wavelength of 2.5~25μm and a power of 30~70 W.

3. The method for infrared laser-assisted mechanical debonding according to claim 1, characterized in that, The scanning width of the infrared laser does not exceed the effective cell of the wafer; The scanning angle of the infrared laser is 1~360°; The scanning rate of the infrared laser is 50~1000 mm / s.

4. The method for infrared laser-assisted mechanical debonding according to claim 1, characterized in that, The mechanical debonding method includes: Fix the wafer and wafer substrate, apply a pulling force to the wafer and / or wafer substrate, and lift the wafer substrate at a constant speed until the wafer and wafer substrate are completely separated.

5. The method for infrared laser-assisted mechanical debonding according to claim 4, characterized in that, The tensile force is 20~60 N; The rise rate of the wafer substrate is 0.1~0.5 mm / s.

6. The method for infrared laser-assisted mechanical debonding according to claim 4, characterized in that, During the mechanical debonding process, shear force is applied by vibration to assist debonding.

7. The method for infrared laser-assisted mechanical debonding according to claim 1, characterized in that, The wafer substrate is made of an infrared-transmitting material.

8. The method for infrared laser-assisted mechanical debonding according to claim 1, characterized in that, The infrared effect adhesive comprises a host resin, a catalyst, an inhibitor, and a solvent.

9. The method for infrared laser-assisted mechanical debonding according to claim 8, characterized in that, The main resin includes vinyl-containing polysiloxane and hydrogen-containing polysiloxane; The viscosity of the vinyl-containing polysiloxane is 100~2000 mPa·s; The hydrogen-containing polysiloxane Si-H group content is 0.1~1.5 mol%; The main resin is selected from Si-H group to vinyl group in a molar ratio of (0.5~2):

1.

10. The method for infrared laser-assisted mechanical debonding according to claim 8, characterized in that, The infrared effect adhesive also includes an infrared laser response-enhancing resin; The infrared laser response-enhancing resin includes epoxy-modified polysiloxane, wherein the epoxy equivalent of the epoxy-modified polysiloxane is 200~1000 g / eq. The infrared laser response-enhancing resin content in the infrared effect adhesive is 0~20 wt%.

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