Temporary bonding adhesive composition

Abstract

An adhesive composition has: (a) linear terminal alkenyl-functional siloxane; (b) alkenyl functional siloxane resin; (c) optionally, a polysiloxane comprising alkenyl-functional D siloxane units; (d) a linear silicone oligomer with (Ph2SiO2 / 2) and / or ((CH3)PhSiO2 / 2) siloxane units, (e) optionally, an additional siloxane crosslinker other than (d) that contains at least two SiH groups provide that the wt%(d) / [wt%(d)+wt%(e)] is in a range of 0.5-1.0; (f) hydrosilylation catalyst; (g) hydrosilylation inhibitor; and (h) solvent; where the adhesive composition has a SiH / Vi molar ration in a range of 0.15 to less than 1.0; and the wt% of vinyl groups from components (b) and (c) relative to the combined weight of component (b) and (c) is in a range of 3.5 to 10.0.

Description

[0001] TEMPORARY BONDING ADHESIVE COMPOSITION

[0002] FIELD

[0003] The present invention relates to a temporary silicone bonding adhesive composition that is particularly useful for temporarily bonding a thin device to a carrier substrate while processing the device.

[0004] INTRODUCTION

[0005] Within a number of industries, there is growing interest in the use of flexible and / or very thin substrates, for example, stainless steel, silicon wafers, glass, ceramic, polyimide and polyester films. Flexible and very thin substrates can be too fragile to be handled freestanding in downstream manufacturing conditions, and must be supported on a suitable carrier to survive. After the fabrication processes are done, the substrate must be removable from the carrier undamaged, preferably at ambient temperature.

[0006] In the electronics industry, as one example, imaging displays, sensors, photovoltaics and RFIDs, increasingly require thin and / or flexible substrates for display applications. An exemplary substrate is a very thin (100 micrometer) glass packed with functionalities. The glass is processed at 300 to 500 degrees Celsius (°C) when depositing thin film transistors (TFT) or at 150-400 °C when depositing indium tin oxide (ITO) as a transparent conductor. Due to the fragility of the glass and the harsh process conditions, this glass must be reinforced or protected by bonding to a more stable substrate during fabrication. Also in a piece-type approach to touch sensor manufacture, touch sensor glasses are pre-cut and bound to a carrier before deposition processes like those described above. Other industries such as silicon wafer manufacturing also require bonding to a carrier substrate to protect increasingly thin silicon wafers during the back grinding process, followed by subsequent clean release.

[0007] Applications such as those described above require a temporary adhesive that is easily and cleanly de-bondable, that permits temporary bonding at processing conditions, and that does not compromise handling or performance of the substrates. In other words, adhesives suitable for temporary bonding applications, which can later be removed at room temperature without causing damage to the target component, would therefore advance the use of thinner or more flexible substrates across various industries.

[0008] However, most currently available adhesives are not cleanly de-bondable from devices such as imaging display, sensors, photovoltaics, and semiconductors, and as a result tend to result in undesirable cohesive failure of the adhesive or leaving undesirable residual adhesive on the surface of devices. Cohesive failure of the adhesive and residual adhesive on the devicesurface required a cleaning process to remove the adhesive from the device surface before moving forwards in the process, which adds complexity to the process and risks damage the surface of device.

[0009] US20230002647 discloses a temporary adhesive that says provides the ability to peel away a wafer from a carrier substrate without leaving adhesive residue on the wafer. However, the adhesive composition requires a non-functional organopolysiloxane, which can detrimentally migrate or bleed through the adhesive during processing. Therefore, it would be desirable to avoid the need for a non-functional organopolysiloxane in the temporary adhesive.

[0010] SUMMARY

[0011] The present invention provides a composition suitable for use as a temporary adhesive suitable for use in manufacturing thin substrate devices for the electronics industry. Moreover, the present invention provides such a composition that has the following targe adhesive properties: (i) is a clear homogeneous solution; (ii) that can be coated onto a thin device substrate; (iii) can be cured to form an adhesive and bonded to a carrier substrate with an adhesion strength of at least 0.2 Newtons per square millimeter (N / mm2) and that allows for debonding of the thin device from the carrier substrate at 23-27 °C without experiencing adhesive residue on the thin device. The composition of this invention allows such results even without the presence of non-functional organopolysiloxane in the adhesive. Even more, the present invention provides a composition suitable for use as a single-layer temporary adhesive suitable for use in manufacturing thin substrate devices for the electronics industry. A singlelayer temporary adhesive offers manufacturing process advantages over multi-layer temporary adhesives by simplifying the process with having to use only a single adhesive composition rather than multiple.

[0012] The present invention is a result of discovering that a temporary adhesive composition comprising a vinyl-functional linear siloxane, a vinyl functional MQ resin, and a silicone oligomer having a silicon-bound hydrogen atom (SiH) that also contains phenyl functionality will result in the aforementioned target adhesive properties. Without being bound by theory, the SiH and phenyl functional silicone oligomer may actually induce some degree of phase separation in the adhesive that facilitates a clean debonding from a thin device substrate even at temperatures of 23-25 °C (room temperature). Even more, the adhesive composition of the present invention does not require a non-functional organopolysiloxane and can be free of nonfunctional organopolysiloxanes while achieving all of these properties.In a first aspect, the present invention is an adhesive composition comprising the following components: (a) 5 to 30 weight-percent of a linear terminal alkenyl-functional siloxane comprising (R12SiO1 / 2) and (R1R2SiO2 / 2) siloxane units and that contains 0.01 to 1.0 weight-percent vinyl groups based on molecular weight of the linear terminal alkenyl-functional siloxane and that is free of silicon-bound aryl functionality; (b) 57 to 75 weight-percent of an alkenyl-functional siloxane resin comprising (R13SiO1 / 2), (R12R2SiO1 / 2) and (SiO4 / 2) siloxane units; (c) 0 to 10 weight-percent of a polysiloxane comprising (R1R2SiO2 / 2) siloxane units, that is free of (R^SiC^) siloxane units, and that contains 27 to 31 weight-percent vinyl groups based on molecular weight of the polysiloxane; (d) 2.5 to 30 weight-percent of a linear silicone oligomer component that comprises one or more than one linear silicone oligomer that have (Ph2SiO2 / 2) and / or ((CH3)PhSiO2 / 2) siloxane units, provided that the average number of (Ph2SiO2 / 2) and ((CH3)PhSiO2 / 2) siloxane units per oligomer molecule in the linear silicone oligomer component is 1.5 or more and the silicone oligomer component has an average of two or more silicon-bound hydrogen atoms per molecule, where Ph refers to a phenyl group; (e) optionally, an additional siloxane crosslinker outside the composition scope of component (d) and that contains two or more silicon-bound hydrogen atoms per molecule, where the weight-percent of component (e) is such that the wt% of component (d) divided by the sum of the weight-percent values for components (d)+(e) has a value in a range of 0.5 to 1.0; (f) 0.5 to 100 weight parts per million weight parts of adhesive composition of the platinum-group metal of a hydrosilylation catalyst; (g) 5 to 10,000 weight parts per million weight part of adhesive composition of a hydrosilylation inhibitor; and (h) 1 to 200 weight-percent solvent; where: (i) weight-percent values are relative to the combined weight of components (a)-(g) unless otherwise stated; (ii) R1refers to C1-C10 alkyl groups and R2refers to C2-C10 alkenyl groups with terminal carbon-carbon double bonds; (iii) the adhesive composition has a SiH / Vi molar ratio in a range of 0.15 to less than 1.0; and (iv) the weight-percent of vinyl groups from components (b) and (c) relative to the combined weight of components (b) and (c) is in a range of 3.5 to 10.0.

[0013] In a second aspect, the present invention is a process for using the adhesive composition of the first aspect, the process comprising the following steps: (a) coating the adhesive composition onto a device substrate to form a coated device substrate; (b) heating the coated device substrate to remove solvents from the adhesive composition to form a dried adhesive composition on the coated device substrate; (c) placing a carrier substrate in contact with thedried adhesive composition to form a laminate comprising the device substrate, dried adhesive composition, and carrier substrate; and (d) separating the device substrate from the carrier substrate.

[0014] The adhesive composition of the present invention is useful as a temporary adhesive between a thin device component and a carrier substrate. The process of the present invention is useful for adhering a device component to a carrier substrate.

[0015] DETAILED DESCRIPTION

[0016] Test methods refer to the most recent test method as of the priority date of this document when a date is not indicated with the test method number. References to test methods contain both a reference to the testing society and the test method number. The following test method abbreviations and identifiers apply herein: ASTM refers to ASTM International methods; END refers to European Norm; DIN refers to Deutsches Institut fur Normung; ISO refers to International Organization for Standards; and UL refers to Underwriters Laboratory.

[0017] Products identified by their tradename refer to the compositions available under those tradenames on the priority date of this document.

[0018] “Multiple” means two or more. “And / or” means “and, or as an alternative”. All ranges include endpoints unless otherwise indicated.

[0019] Polysiloxanes (“siloxanes”, or “silicones”) comprise multiple siloxane units linked together through siloxane bonds. Siloxane units can be characterized by the designation M, D, T or Q. Unless stated otherwise: “M” correspond to R3SiO1 / 2siloxane units. “D” corresponds to R2SiO2 / 2. “T” corresponds to RSiOs / 2 siloxane units. “Q” corresponds to SiO.4 / 2 siloxane units. Notably, an oxygen atom having a multiple of “1 / 2” subscript is an oxygen of a siloxane bond that is shared with a silicon atom of two siloxane units including the one of the subject siloxane unit and another having an oxygen atom with a 1 / 2 subscript designation.. The numerator of the subscript indicates how many shared oxygen atoms are attached to the silicon atom. For example, SiOs / 2 has three siloxane bonded oxygen atoms that are shared with other siloxane units. Unless otherwise indicated, each R group is selected from hydrogen (H), hydroxyl (-OH), alkoxyl (-OR), hydrocarbyl groups and substituted hydrocarbyl groups. Silicon-bound hydroxyl (Si-OH) and alkoxy (Si-OR) groups are collectively called “OZ” groups. In specifying a polysiloxane chemical formula, the amount of each siloxane unit is indicated by a subscript following the siloxane unit. When any of the subscripts in a chemical formula are less than 1.00, then the subscripts correspond to the mole ratio of the associated siloxane units in the chemical formula relative to total moles of siloxane units. When there are any subscripts greater than1.00, then the subscript corresponds to the average number of those siloxane units in the chemical formula. Determine siloxane unit compositions of polysiloxanes using29Si NMR methods.

[0020] A siloxane resin (or silicone resin) refers to a polysiloxane containing T and / or Q siloxane units such that the sum of any T and Q siloxane units in the polysiloxane account for greater than 30 mol-percent (mol%), typically 50 mol% or more, relative to total moles of siloxane units in the polysiloxane.

[0021] Determine number average molecular weight (Mn), weight-average molecular weight (Mw) and molecular weight distribution of siloxanes by gel phase chromatography (GPC) using an Agilent Technologies 1260 Infinity chromatograph and ethyl acetate as a solvent. The chromatograph uses two columns, Agilent PLgel Mixed-D and PLgel Mixed E columns.

[0022] Calibrate the chromatograph using polystyrene standards over a range of 2,000 to 30,000.

[0023] Prepare samples by dissolving sample material in toluene (approximately 20 milligrams per milliliter) and then immediately analyzing the material by GPC using a flow rate of one milliliter per minute and a column temperature of 35 degrees Celsius (°C).

[0024] “Silyl hydride” functionality refers to having a hydrogen atom bonded directly to a silicon atom to form an SiH group.

[0025] Cx-Cyand Cx-yrefer to having from x to y carbon atoms where x and y are stated as numbers. Cxrefers to having x carbon atoms, where x is stated as a number.

[0026] In a first aspect, the present invention is an adhesive composition. An adhesive composition is a curable composition that can be cured to form an adhesive. The adhesive composition of the present invention is curable by hydrosilylation chemistry. The adhesive composition can be free of epoxy-modified polyorganosiloxane. The adhesive composition can be free of non-functional organopolysiloxanes.

[0027] The adhesive composition is a clear homogeneous solution that can be coated onto a surface. Clear and homogeneous means that there is no visible inhomogeneity (separation or turbidity) in a sample of the adhesive composition after sitting for 24 hours at 25 °C. If an adhesive composition is not clear and homogeneous then it is difficult to coat the composition evenly onto a substrate.

[0028] The adhesive composition comprises components (a)-(h) as described below. Unless otherwise stated, weight-percent (wt%) values for components of the adhesive composition herein are relative to the combined weight of component (a)-(g), but does not include solvent component (h). For example, wt% of component (a) in a formulation = 100 x [weight ofcomponent (a)| / |sum of the weights of components (a)-(g) ]. Similarly, the wt% for component (h) = 100 x [weight of component (h)] / [sum of the weights of components (a)-(g)] even though component (h) is not included in the denominator.

[0029] (a) Linear Terminal Alkenyl-Functional Siloxane

[0030] The linear terminal alkenyl-functional siloxane comprises and can consist of (R12SiO2 / 2) and (R1R2SiO2 / 2) siloxane units, where each R1independently is selected from C1-10alkyl groups and each R2is independently selected from C2-10alkenyl groups. Desirably, R1is selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl and octyl groups. R1can be methyl in each occurrence. Desirably, R2is selected from vinyl, allyl, and hexenyl groups. The alkenyl groups are “terminal” alkenyl groups, which means there is a carbon-carbon double bond at the end of a carbon chain thereby forming a vinyl group (-CH=CH2) at the end of the carbon chain. The linear terminal alkenyl-functional siloxane can be free of SiH groups.

[0031] The linear terminal alkenyl-functional siloxane contains 0.01 to 1.0 weight-percent (wt%) and can contain 0.01 wt% or more, 0.02 wt% or more, 0.04 wt% or more, even 0.06 wt% or more, while at the same time contain 1.0 wt% or less, 0.90 wt% or less, 0.50 wt% or less, 0.20 wt% or less, 0.10 wt% or less, or even 0.065 wt% or less of terminal vinyl groups based on molecular weight of the linear terminal alkenyl-functional siloxane.

[0032] The linear terminal alkenyl-functional siloxane is free of aryl functionality.

[0033] The linear terminal alkenyl-functional siloxane can be selected from organosiloxanes having an average chemical formula (I):

[0034] (R12R2SiOl / 2)2(R12SiO2 / 2)d(R1R2SiO2 / 2)d’ (I) where:

[0035] R1independently in each occurrence is as previously described herein.

[0036] R2independently in each occurrence is as described previously herein, and can be selected from vinyl, allyl, and hexenyl groups.

[0037] subscript d has a value in a range of 1000 to 8000, and can be 1000 or more, 2000 or more, 3000 or more, 4000 or more, 4500 or more, 4800 or more, 5000 or more, 5400 or more, 5600 or more, even 5800 or more, while at the same time is typically 8000 or less, 7000 or less, 6000 or less, or even 5900 or less.

[0038] subscript d' has a value in a range of 0 to 50. and can be 0 or more, 5 or more, 7 or more, 10 or more, 15 or more, even 20 or more, while at the same time is typically 50 or less, 40 or less, 30 or less, and can be 25 or less.Examples of suitable linear terminal alkenyl-functional siloxanes include any one or any combination of more than one of the following: dimethylvinylsiloxy-terminated polydimethyl siloxane; dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylvinylsiloxane); dimethylvinylsiloxy-terminated polymethylvinylsiloxane; trimethylsiloxy -terminated poly(dimethylsiloxane / methylvinylsiloxane); dimethylhexenylsiloxy-terminated polydimethylsiloxane); dimethylhexenylsiloxy-terminated poly(dimethylsiloxane / methylhexenylsiloxane); dimethylhexenylsiloxy-terminated polymethylhexenylsiloxane; and dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylhexenylsiloxane). Linear terminal alkenyl -functional siloxanes can be prepared according to teachings in, for example, US3284406; US4772515; US5169920; 5317072; and US6956087. Commercial examples of linear terminal alkenyl-functional siloxanes include those available from Gelest under the names: DMS-V00; CMS-V03; DMS-V05; DMS-V21; DMS-V22; DMS-V25; DMS-V31; DMS-V33; DMS-V34; DMS-V35; DMS-V41; DMS-V42; DMS-V43; DMS-V46; DMS-V51; and DMS-V52.

[0039] The concentration of the linear terminal alkenyl-functional siloxane is typically 5 to 30 wt%, and can be 5 wt% or more, 7 wt% or more, 8 wt% or more, 10 wt% or more, 12 wt% or more, 14 wt% or more, even 16 wt% or more, while at the same time is typically 30 wt% or less, and can be 25 wt% or less, 20 wt% or less, 19 wt% or less, 18 wt% or less, 17 wt% or less, 16 wt% or less, even 15 wt% or less with wt% values of linear terminal alkenyl-functional siloxane relative to the combined weight of components (a)-(g) in the adhesive composition.

[0040] (b) Alkenyl-Functional Siloxane Resin

[0041] The alkenyl-functional siloxane resin contains (

[0042]

[0043] RSSiOj^), (R^R^iOj^) and (SiOa / 2) siloxane units, where R and R are as described previously herein. The alkenyl-functional siloxane resin is desirably free of SiH groups. The alkenyl-functional siloxane resin can be selected from those having an average chemical formula (II):

[0044] (R13SiOi / 2)m(R12R2SiOi / 2)m’(SiO4 / 2)q(II) where:

[0045] R1and R2are as described previously herein;

[0046] subscript m has a value in a range of 0.25 to 0.50, and can have a value of 0.30 or more, 0.33 or more, 0.35 or more, even 0.37 or more, while at the same time is typically 0.50 or less, and can be 0.45 or less, 0.42 or less; 0.40 or less, 0.38 or less, 0.36 or less, or even 0.34 or less;subscript m’ has a value in a range of 0.02 to 0.20, and can have a value of 0.02 or more, 0.05 or more, even 0.09 or more, while at the same time is typically 0.20 or less, and can be 0.15 or less, 0.13 or less, 0.11 or less, even 0.10 or less;

[0047] subscript q has a value in a range of 0.45 to 0.60, and can have a value of 0.45 or more, 0.48 or more, 0.49 or more, 0.50 or more, 0.52 or more, 0.54 or more, even 0.55 or more, while at the same time is typically 0.60 or less, and can be 0.59 or less, 0.58 or less, 0.57 or less, 0.56 or less, even 0.55 or less;

[0048] where the sum of m+m’+q equals 1.00.

[0049] At the same time, the alkenyl-functional siloxane resin desirably has:

[0050] a number-average molecular weight (Mn) that is in a range of 2,000 to 6,000, and can have a Mn of 2,000 or more, 2,500 or more, even 3,000 or more, while at the same time 6,000 or less, and can be 5,500 or less, even 5,000 or less; and

[0051] a weight-average molecular weight (Mw) that is in a range of 4,000 to 25,000 and can be 4,000 or more, 4,500 or more, 5,000 or more, even 5,500 or more, while at the same time is typically 25,000 or less, and can be 20,000 or less.

[0052] Typically, the alkenyl-functional siloxane has an vinyl group concentration that is 1.2 to 5.0 wt%, and can be 1.2 wt% or more, 1.4 wt% or more, 1.6 wt% or more, 1.8 wt% or more, 2.0 wt% or more, 2.5 wt% or more, even 3.0 wt% or more, while at the same time is typically 5.0 wt% or less, and can be 4.5 wt% or less, 4.3 wt% or less, 4.1 wt% or less, 3.9 wt% or less, 3.7 wt% or less, even 3.5 wt% or less, with wt% relative the weight of the alkenyl-functional siloxane.

[0053] The alkenyl-functional siloxane can be prepared according to teachings in, for example, US2676182; US4611042; and US4774310. Commercially available samples of alkenyl-functional siloxanes include those available from Gelest under the name VQX-135; VQX-221; and VQM-146.

[0054] Suitable alkenyl-functional siloxanes include those having the following molecular formulae: (Me3SiOi / 2)o.34(ViMe2SiOi / 2)o.n(Si04 / 2)o.55 with Mn=5,000, Mw=20,000, and 4.1 wt% Vi; (Me3SiOi / 2)o.38(ViMe2SiOi / 2)o.o4(Si04 / 2)o.58 withMn= 5,000, Mw=20,000, and 1.6 wt% Vi; and (Me3SiOi / 2)o.4o(ViMe2SiOi / 2)o.io(Si04 / 2)o.50 with Mn=3,000, Mw=5,500, and 3.4 wt% Vi; where “Vi” herein refers to vinyl groups and “Me" refers to methyl groups..

[0055] The concentration of the alkenyl -functional siloxane resin is typically 57-75 wt%, and can be 57 wt% or more, 59 wt% or more, 60 wt% or more, 61 wt% or more, 62 wt% or more, 63 wt% or more, 64 wt% or more, even 65 wt% or more, while at the same time is typically 75 wt%or less, and can be 73 wt% or less, 70 wt% or less, 69 wt% or less, 68 wt% or less, 67 wt% or less, 66 wt% or less, or even 65 wt% or less, with wt% relative to the combined weight of components (a)-(g) in the adhesive composition.

[0056] (c) Optional Poly siloxane with Alkenyl-D siloxane Units

[0057] The adhesive composition optionally comprises a polysiloxane comprising (R1R2SiO2 / 2) siloxane units and free of (R12SiO2 / 2) siloxane units, where R and R“ are as described previously herein. The molecular weight of component (c) is typically less than that of component (a). Moreover, the concentration of vinyl groups is much higher for component (c) than component (a). Typically, component (c) comprises 27 to 31 wt% vinyl groups based on molecular weight of component (c), and can contain 27 wt% or more, 28 wt% or more, even 29 wt% or more, while at the same time typically contain 31 wt% or less, and can contain 30 wt% or less vinyl groups based on molecular weight of component (c). Component (c) desirably is free of SiH functionality.

[0058] Component (c) can be selected from cyclic siloxanes having a formula: (R1R2SiO2 / 2)nwhere subscript n has a value in a range of 3-20. Preferably, subscript n has a value of 3 or more, and can be 4 or more, while at the same time is typically 20 or less, and can be 15 or less, 10 or less, 8 or less, 6 or less, even 4 or less. Most preferably, n is 4.

[0059] In addition to, or alternative to the cyclic options, component (c) can be selected from siloxane have an average chemical formula (III):

[0060] (R1R2(OZ)SiOi / 2)2(R1R2SiO2 / 2)d’ (III) where: Z refers to a hydrogen or hydrocarbyl; R1and R2as described herein above; and subscript d’ has a value in a range of 3 to 20, and can have a value of 3 or more, 4 or more, 5 or more, 6 or more, even 7 or more, while at the same time typically has a value of 20 or less, 15 or less, 10 or less, 9 or less, or even 8 or less.

[0061] Component (c) can be desirable to increase the concentration of vinyl groups in the adhesive formulation. If the concentration of vinyl groups in component (b) is less than 3.5 wt% of the molecular weight of component (b), then it is desirable to increase the concentration of vinyl groups using component (c) enough so that the wt% of vinyl groups from components (b) and (c) relative to the combined weight of components (b) and (c) (i.e., Vi(b+c)) is at least 3.5 wt% and preferably in a range of 3.5 to 10 wt%. Desirably, the wt% of vinyl groups from components (b) and (c) is in a range of 3.5 to 10 wt%, and can be 3.5 wt% or more, 3.8 wt% or more, 4.0 wt% or more, even 4.1 wt% or more, while at the same time is generally 10.0 wt% or less, and can be 9.0 wt% or less, 8.0 wt% or less, 7.0 wt% or less, 6.0 wt% or less, 5.0 wt% orless, even 4.5 wt% or less, with wt% referring to wt% of vinyl groups from components (b) and (c) based on the combined weights of (b) and (c). Determine Vi(b+c)using the following formula:

[0062] wt% Vi(b+c)= [ (Vi% (b))*(wt% (b)) + (Vi% (c))* (wt% (c)) ] / [wt% (b) + wt% (c)] where “Vi%(b)” refers to the wt% Vi in component (b); “Vi% (c)” refers to the wt% vinyl in component (c); “wt% (b)” refers to the wt% of component in the adhesive formulation; and “wt% (c)” refers to the wt% of component (c) in the adhesive formulation.

[0063] Component (c) can be made according to processing taught in, for example, US3284406; US4772515; US5169920; US5317072; and US6956087. Commercially available materials suitable as component (c) include those available from Gelest under the names VMM-010; VEE-055; SIT7900.0; and SIP6719.7.

[0064] Typically, the concentration of component (c) is present at a concentration in a range of 0-10 wt%, and can be 0 wt% or more, even 1.0 wt% or more, while at the same time is typically 10 wt% or less, 9 wt% or less, 8 wt% or less, 7 wt% or less, 6 wt% or less, 5 wt% or less, 4 wt% or less, 3 wt% or less, 2 wt% or less even 1 wt% or less, with wt% relative to the combined weight of components (a)-(g) in the adhesive composition.

[0065] (d) Phenyl-Functional and SiH-Functional Linear Silicone Oligomer Component Component (d) is a linear silicone oligomer component that comprises one or more than one linear silicone oligomer that have (Ph2SiO2 / 2) and / or (MePhSiC>2 / 2) siloxane units, provided that the average number of (Ph2SiO2 / 2) and (MePhSiO2 / 2) siloxane units per oligomer molecule in the linear silicone oligomer component is 1.5 or more and the linear silicone oligomer component has an average of two or more silicon-bonded hydrogen atoms (SiH groups) per molecule, where Ph refers to a phenyl group and Me refers to a methyl group. Desirably, component (d) is free of terminal alkenyl groups and can be free of any alkenyl groups.

[0066] Component (d) is necessary to achieve the surprisingly selective delamination of a thin device substrate from the cured adhesive composition holding the device substrate to a carrier substrate. Without being bound by theory, component (d) may actually induce some degree of phase separation in the adhesive that facilitates a clean debonding from a thin device substrate even at temperatures of 23-25 °C (room temperature).

[0067] Component (d) can be a single oligomer or a combination of oligomers. On average, the number of (Ph2SiO2 / 2) and ((CH3)PhSiO2 / 2) siloxane units per molecule in the oligomer, or as an average over multiple oligomers if multiple oligomers are present having (Ph2SiO2 / 2) and / or((CHs)PhSiO2 / 2) siloxane units, is 1.5 or more, and can be 2 or more, 2.5 or more, even 3 or more, while at the same time is typically 10 or less, 8 or less, 6 or less, 5 or less, 4 or less, even 3 or less. To be clear, the linear silicone oligomer component (d) does not require both (Ph2SiO2 / 2) and (MePhSiO2 / 2) siloxane units, but can contain both (Ph2SiO2 / 2) and (MePhSiO2 / 2) siloxane units. If component (d) only has (Ph2SiO2 / 2) siloxane units, then the average number of (Ph2SiO2 / 2) siloxane units is in the aforementioned range. If component (d) only has (MePhSiO2 / 2) siloxane units, then the average number of (MePhSiO2 / 2) siloxane units is in the aforementioned range. If component (d) has both (Ph2SiO2 / 2) siloxane units and (MePhSiO2 / 2) siloxane units, then the average number of (Ph2SiO2 / 2) siloxane units and (MePhSiO2 / 2) siloxane units combined is in the aforementioned range.

[0068] Component (d) can be selected from one or more than one oligomer having an average chemical formula (IV):

[0069] (HR12SiOi / 2)2(Ph2SiO2 / 2)d”(MePhSiO2 / 2)d”’ (IV) where: R1is as described herein above; “Ph” refers to a phenyl group; and subscript d” has an average value in a range of zero to 10, subscript d’” has a value in a range of zero to 10, and provided that the sum of d” and d’” has a value in a range of 1 to 10, and can be 1 or more, 1.5 or more, 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, even 8 or more, while at the same time is typically 10 or less, and can be 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, 3 or less, even 2 or less, provided that the average value for the sum of d” and d’” over all oligomers of formula (IV) in component (d) is 1.5 or more.

[0070] For example, component (d) can be a combination of three oligomers, each having an average chemical formula that is within the scope of chemical formula (IV):

[0071] Oligomer 1: (HR12SiOi / 2)2(Ph2SiO2 / 2)i

[0072] Oligomer 2: (HR¹₂SiO1 / 2)2(Ph2SiO2 / 2)2

[0073] Oligomer 3: (HR¹₂SiO1 / 2)2(Ph2SiO2 / 2)3

[0074] The combination of Oligomers 1, 2 and 3 can be, for example, such that the average value for d” for the combination of oligomers is 1.7, 2.3, or 2.6. Such a combination is acceptable as component (d).

[0075] Methods for making materials suitable as component (d) include those in Chem. Rev.

[0076] 2009, 109:897-1091; Macromol Rapid Commun 2007, 28:1676-702; and Chem Rev 2006; 106:5028-48.The concentration of component (d) in the adhesive composition is desirably in a range of 2.5 to 30 wt%, and can be 2.5 wt% or more, 3 wt% or more, 4 wt% or more, 5 wt% or more, 6 wt% or more, 7 wt% or more, 8 wt% or more, 9 wt% or more, 10 wt% or more, 11 wt% or more, 12 wt% or more, 14 wt% or more, 16 wt% or more, 18 wt% or more, even 20 wt% or more, while at the same time is typically 30 wt% or less, and can be 28 wt% or less, 26 wt% or less, 24 wt% or less, 22 wt% or less, 20 wt% or less, 18 wt% or less, 16 wt% or less, 14 wt% or less, 12 wt% or less, 10 wt% or less, 8 wt% or less, 6 wt% or less, even 4 wt% or less, with wt% relative to the combined weight of components (a)-(g) in the adhesive composition.

[0077] (e) Optional Additional Siloxane Crosslinker

[0078] The adhesive composition optionally contains an additional siloxane crosslinker that is outside the composition scope of component (d) and that contains two or more silicon-bound hydrogen atoms (SiH groups) per molecule. In other words, component (e) contains two or more SiH groups, but does not have an average of more than one (Ph2SiO2 / 2) and / or (MePhSiO2 / 2) siloxane units per molecule. Some examples of suitable additional siloxane crosslinkers include dimethylhydrogen-terminated phenyl silsesquioxane and trimethylsilyl-terminated dimethylsiloxane-co-methylhydrosiloxane copolymer.

[0079] Dimethylhydrogen-tenuinated phenyl silsesquioxane includes siloxanes having a general chemical formula: [H(CH3)2SiOi / 2]m’[PhSiO3 / 2]t’, where subscript m’ has a value of 20 or more, and can be 30 or more, 40 or more, 50 or more, even 60 or more, while at the same time is typically 80 or less, 70 or less, even 60 or less; and where subscript t’ has a value that is 20 or more, 30 or more, even 40 or more, while at the same time is typically 60 or less, 50 or less, even 40 or less.

[0080] Trimethylsilyl-terminated dimethylsiloxane-co-methylhydrosiloxane copolymer includes siloxanes having a general chemical formula: [(CH3)3SiOi / 2]2[(CH3)2SiO2 / 2]a[H(CH3)SiO2 / 2]b where subscript a has a value of 1 or more, and can be 2 or more, 3 or more, even 4 or more, while at the same time is typically 8 or less, 7 or less, 6 or less, 5 or less, or even 4 or less; and subscript b has a value of 2 or more, and can be 3 or more, 4 or more, 5 or more, even 6 or more, while at the same time is typically 10 or less, 9 or less, 8 or less, 7 or less, or even 6 or less.

[0081] The concentration of component (e) is such that the wt% of component (d) divided by the sum of the wt% of components (d) and (e) has a value in a range of 0.5 to 1.0, and can be 0.5 or more, 0.6 or more, 0.7 or more, 0.8 or more, even 0.9 or more, while at the same time is 1.0 or less, and can be 0.9 or less, 0.8 or less, or even 0.7 or less.The concentrations of components (a), (b), (c), (d), and (e) are such that the mole ratio of SiH groups to vinyl groups (SiH / Vi) in the adhesive composition is in a range of 0.15 to less than 1.0, and can be 0.15 or more, 0.20 or more, 0.30 or more, 0.40 or more, 0.50 or more, 0.60 or more, 0.70 or more, 0.80 or more, even 0.90 or more, while at the same time is less than 1.00, and can be 0.95 or less, 0.90 or less, 0.85 or less, 0.80 or less, 0.75 or less, 0.70 or less, 0.65 or less, 0.60 or less, 0.55 or less, even 0.50 or less.

[0082] (f) Hydrosilylation Catalyst

[0083] In the broadest scope, the hydrosilylation catalyst can be any catalyst known to catalyze hydrosilylation reactions. Hydrosilylation catalyst include platinum group metals such as platinum, rhodium ruthenium, palladium, osmium, and iridium as well as organometallic compounds of platinum group metals. Typically, the catalyst is a complex of platinum.

[0084] Platinum-based hydrosilylation catalysts include compounds and complexes such as platinum (0)-l,3-divinyl-l,l,3,3-tetramethyldisiloxane (Karstedt’s catalyst), H2PtC16, di-p. -carbonyl di-.7i.-cyclopentadienyldinickel, platinum-carbonyl complexes, platinum-divinyltetramethyldisiloxane complexes, platinum cyclovinylmethylsiloxane complexes, platinum acetylacetonate (acac), platinum black, platinum compounds such as chloroplatinic acid, chloroplatinic acid hexahydrate, a reaction product of chloroplatinic acid and a monohydric alcohol, platinum bis(ethylacetoacetate), platinum bis(acetylacetonate), platinum dichloride, and complexes of the platinum compounds with olefins or low molecular weight organopolysiloxanes or platinum compounds microencapsulated in a matrix or core-shell type structure. The hydrosilylation catalyst can be part of a solution that includes complexes of platinum with low molecular weight organopolysiloxanes that include 1,3-diethenyl-l, 1,3,3-tetramethyldisiloxane complexes with platinum. These complexes may be microencapsulated in a resin matrix. The catalyst can be l,3-diethenyl-l,l,3,3-tetramethyldisiloxane complex with platinum.

[0085] The concentration of the hydrosilylation catalyst is sufficient to provide platinum group metal is at a concentration in a range of 0.5 to 100 weight parts per million weight parts of the combined weights of components (a)-(g) in the adhesive composition (ppm), and can be 0.5 ppm or more, 0.75 ppm or more, 1.0 ppm or more, 2 ppm or more, 5 ppm or more, 10 ppm or more, 20 ppm or more 30 ppm or more, 40 ppm or more, even 50 ppm or more, while at the same time is typically 100 ppm or less, and can be 90 ppm or less, 80 ppm or less, 70 ppm or less, 60 ppm or less, even 50 ppm or less.(g) Hydrosilylation Inhibitor

[0086] The adhesive composition comprises a hydrosilylation inhibitor to provide shelf stability and handling stability to the adhesive composition by preventing premature curing of the adhesive composition. Suitable hydrosilylation inhibitors, in the broadest scope, can be any known hydrosilylation inhibitors. Examples of suitable hydrosilylation inhibitors include any one or any combination or more than one of the following: alkyne alcohols such as 2-methyl-3-butyn-2-ol, 3,5-dimethyl-l-hexyn-3-ol, or 2-phenyl-3-butyn-2-ol, 1-ethynyl-cyclohexan-l-ol; an ene-yne compound such as 3-methyl-3-penten-l-yne or 3,5-dimethyl-3-hexen-l-yne; or 1,3,5,7-tetramethyl-l,3,5,7-tetravinylcyclotetrasiloxane, l,3,5,7-tetramethyl-l,3,5,7-tetrahexenylcyclotetrasiloxane, tris[(l,l-dimethyl-2-propynyl)oxy]methylsilane, diallyl maleate, benzotriazole and thiram derivatives.

[0087] The amount of hydrosilylation reaction inhibitor is typically in a range of 1 to 10,000 weight parts per one million weight parts of the combined weights of components (a)-(g) in the adhesive composition (ppm), and can be 1 ppm mor more, 10 ppm or more, 100 ppm or more, 500 ppm or more, 1000 ppm or more, 1500 ppm or more, 2000 ppm or more, 2500 ppm or more, 3000 ppm or more, 4000 ppm or more, even 5000 ppm or more, while at the same time is typically 10,000 ppm or less, and can be 9000 ppm or less, 8000 ppm or less, 7000 ppm or less, 6000 ppm or less, 5000 ppm or less, 4000 ppm or less, 3000 ppm or less, 2500 ppm or less, even 2000 ppm or less.

[0088] (h) Solvent

[0089] The adhesive composition includes solvent that serves as a earner to the other components and facilitate coating the adhesive composition components onto a substrate surface. The solvent can be an organic solvent such as any one or combination of more than one of the following: alcohols, such as methanol, ethanol, isopropanol, butanol, and n-propanol; ketones, such as acetone, methylethyl ketone, and methyl isobutyl ketone; aromatic hydrocarbons, such as benzene, toluene, and xylene; aliphatic hydrocarbons, such as heptane, hexane, oxtane, and p-menthane; glycol ethers, such as propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol n-butyl ether, propylene glycol n-propyl ether, and ethylene glycol n-butyl ether; halogenated hydrocarbons, such a dichloromethane, 1,1,1, -trichloroethane, methylene chloride; chloroform; dimethyl sulfoxide; dimethyl formamide; acetonitrile; tetrahydrofuran: white spirits; mineral spirits; naphtha; and n-methyl pyrrolidone.

[0090] The concentration of solvent in the adhesive composition depends on the deposition method used to coat a substrate surface and the desired thickness of adhesive on that substrate surface. Generally, more solvent is used to achieve a thinner thickness of adhesive on a substratesurface. The amount of solvent is usually in a range of 1 to 200 wt%, and can be 1 wt% or more, 10 wt% or more, 20 wt% or more, 30 wt% or more, 40 wt% or more, 50 wt% or more, 60 wt% or more, 70 wt% or more, 80 wt% or more, 90 wt% or more, even 100 wt% or more, while at the same time is typically 200 wt% or less, 150 wt% or less, 120 wt% or less, 100 wt% or less, 95 wt% or less, and can be 90 wt% or less, 80 wt% or less, 70 wt% or less, 60 wt% or less, 50 wt% or less, 40 wt% or less, 30 wt% or less, 20 wt% or less, even 10 wt% or less, with wt% relative to the combined weight of components (a)-(g) of the adhesive composition.

[0091] In a second aspect, the present invention is a process for using the adhesive composition of the first aspect. The process includes a device substrate and a carrier substrate.

[0092] A device substrate can be any substrate. The device substate is typically a substrate with generally opposing surfaces, meaning surfaces that can be, but are not necessarily exactly parallel to one another but are on opposing sides of the substrate. The process involves applying adhesive to a surface typically to one of the opposing surfaces, of the device substrate and then temporarily adhering that surface to a carrier substrate to form a substrate laminate. This process is particularly valuable for “thin” device substrates to provide support for processing the device substrate to avoid damaging the device substrate during processing. A device substrate is “thin” if the distance between the generally opposing surfaces is sufficiently small that the device risks damage, such as bending or breaking, during desired processing of the device substrate. For example, thin device substrates can have a thickness (distance between generally opposing surfaces) that is less than a millimeter, and can be 100 micrometers or less. Examples of possible desired processing include milling, polishing, patterning circuits onto the device substrate, and / or fabricating electronic articles with the device substrate. Even more valuable is the fact the adhesive composition of the present invention cures to an adhesive that can not only adhere a thin device substrate to a carrier substrate, but upon later separation of the device substrate from the carrier substrate the adhesive remains with the carrier substrate leaving a clean device substrate even when separating the two substrates at room temperature (23-27 °C).

[0093] Typical device substrates are semiconductor wafers, including silicon wafers, germanium wafers, gallium-arsenic wafers, gallium-phosphorous wafers, and gallium-arsenic-aluminum wafers. The thickness of the wafers is not limited in the broadest scope of the present invention, but can be in a range of 400 to 800 micrometers, and can be 400 micrometers or more, 425 micrometers or more, 450 micrometers or more, 500 micrometers or more, 600 micrometers or more, even 625 micrometers or more, while at the same time are typically 800 micrometers or less, and can be 775 micrometers or less, 750 micrometers or less, 700 micrometers or less, 650 micrometers or less, 600 micrometers or less, 550 micrometers or less, 500 micrometers or less,450 micrometers or less, even 425 micrometers or less. The wafers can be as thin as 100 micrometers or less while typically having a thickness of 10 micrometers or more, 50 micrometers or more, even 75 micrometers or more.

[0094] Carrier substrates are also without limitation in the broadest scope of the invention. Examples of suitable carrier substrates include silicone wafers, glass plates, and quarts wafers.

[0095] The process comprises the following steps:

[0096] Step (a): Coating the adhesive composition onto a device substrate to form a coated device substrate. In the broadest scope of the invention, the coating process can be any coating process that involves depositing the adhesive onto a surface of a device substrate. For example, coating the adhesive composition onto a device substrate can occur by using a spin coater (spin coating), gravure coater (gravure coating), offset coater (offset coating), offset-gravure coater (offset-gravure coating), air knife coater (air-knife coating), or curtain coater (curtain coating). Spin coating is particularly desirable for use in the present invention and can use any spin coating processes.

[0097] The thickness of adhesive composition coating the device substrate depends on requirements of a particular application. Generally, the thickness of the adhesive composition coating the device substrate is 5 micrometers or more, and can be 10 micrometers or more, 20 micrometers or more, 30 micrometers or more, 40 micrometers or more, even 50 micrometers or more, while at the same time is typically 500 micrometers or less, and can be 400 micrometers or less, 300 micrometers or less, 200 micrometers or less, 100 micrometers or less, 80 micrometers or less, 60 micrometers or less, even 40 micrometers or less.

[0098] Step (b): heating the coated device substrate to remove solvent(s) from the adhesive composition to form a dried adhesive composition on the coated device substrate. The method of heating is not critical but desirably is done without or with minimal curing of the adhesive composition. Heating in this step can be heating to a temperature of 50 °C or more, 70 °C or more, or even 80 °C or more, while at the same time typically heating to a temperature of 140 °C or lower, 120 °C or lower, even 110 °C or lower while allowing solvent vapor to escape from the adhesive composition. Heating usually occurs for 30 seconds or more, even one minute or more, while at the same time heating generally occurs for one hour or less, preferably 5 minutes or less. Heating can cease once all the solvent is gone from the adhesive composition on the device substrate.

[0099] Step (c): placing a carrier substrate in contact with the dried adhesive composition to form a laminate comprising the device substrate, dried adhesive composition, and carrier substrate. In order to adhere a carrier substate to the device substrate using theadhesive composition, a carrier substrate is place onto the dried adhesive composition that resides on the device substrate.

[0100] Step (d): heating the laminate to cure the dried adhesive composition between the carrier substrate and device substrate. This step is often accomplished in two phases. First, apply pressure to press the two substrates together with the adhesive composition between them, typically but not necessarily while under vacuum, while heating to a relatively mild elevated temperature. The purpose of this phase is to soften the adhesive composition without initiating extensive curing and to eliminate voids in the adhesive composition between the two substrates. Second, heat to a higher temperature in order to cure the adhesive composition between the two substrates.

[0101] In the first phase, heat the laminate to 40 °C or more, 70 °C or more, even 80 °C or more, while at the same time 150 °C or less, even 140 °C or less. A pressure that is 0.01 MegaPascals (MPa) or more, even 0.1 MPa or more, while at the same time is typically 10 MPa or less, and can be 5 MPa or less is typically applied to press the two substrates towards one another with the adhesive composition in between. This phase is also commonly carried out under vacuum to assist in removing voids. The vacuum is typically in a range of 13 Pascals to 0.13 milliPascals. The first phase usually last one minute or more, and at the same time typically lasts 5 minutes or less, even 2 minutes or less.

[0102] In the second phase, heat the laminate to a temperature in a range of 150 to 200 °C, typically for 10 to 60 minutes, to cure the adhesive composition.

[0103] Step (e): Optionally, subjecting the laminated article to a process for modifying the device substrate. An objective of laminating the device substrate to a carrier substrate is to make the device substrate less likely to damage during processing. Once laminated to the carrier substrate, the device substrate opposite the one adhered to the carrier substrate (that is, the back side of the device substrate) can be further processed. Further processing can include grinding, polishing, patterning, and / or chemical vapor deposition.

[0104] Step (f): Separating the device substrate from the carrier substrate. The process for separating the device substrate from the carrier substrate is desirably done under moderate conditions. Examples of method for separating, or releasing, the device substrate from the carrier substrate include pealing the device substrate from the carrier substrate by pulling the carrier substrate away from the device substrate (or vice versa) at an angle to peel them apart. A crack initiator such as those described in WO2013063603, for example a razor blade, can be used to initiate separating the device substrate from the carrier substrate.One of the desirable features of the present adhesive composition is that it can be used as the sole adhesive between a device substrate and a carrier substrate and still hold the substrates together through processing and the allow separation of the substrates when desired in a way that leaves no adhesive reside on the device substrate. Such a clean separation can occur even when the separation takes place at a temperature in a range of 23 to 27 °C.

[0105] EXAMPLES

[0106] Table 1 lists the components for use in preparing the samples that follow. “Me” refers to a methyl group. “Vi” refers to a vinyl group. “Ph” refers to a phenyl group. “OH” refers to a hydroxyl group. DOWSIL is a trademark of The Dow Chemical Company. XIAMETER and SILASTIC are trademarks of Dow Silicones Corporation.

[0107] Preparation of Adhesive Compositions

[0108] Prepare adhesive compositions using the components in the formulations of Tables 2-8 for the compositions listed in those tables. Values for each component in the tables are in wt% relative to the combined weight of components (a)-(g) unless indicated otherwise. Values in ppm are weight-parts are million weight-parts of the combined weight of component (a)-(g) unless otherwise stated. The tables also provide characterization results for Device / Carrier laminates made with the adhesive composition.

[0109] Dissolve component (b) in solvent component (h) to form a mixture. To the mixture, add components (a), (d), (g), (c) if present, and (e) if present). Mix the components together at 23-27 °C. Add component (f) while continuing to mix. Then add in component (g) while mixing and continue mixing for 5 minutes. Save a portion of the resulting adhesive formulation to use to characterize homogeneity as described below. Use the remaining adhesive composition immediately to prepare a device substrate / carrier substrate laminate and then to further characterize the laminate as described below.

[0110] Characterize adhesive composition homogeneity by allowing the adhesive composition to sit at 25 °C for 24 hours and then visually inspect the adhesive composition. If there is no apparent phase separation or turbidity then the adhesive composition is considered homogeneous. If there is phase separation and / or turbidity evident then the adhesive composition is considered non-homogeneous.Table 1

[0111] Component Description Source

[0112] A-l [ViMe2SiOi / 2]2[Me2SiO2 / 2]s462[ViMeSiO2 / 2]7.5 Available under the name having 0.065 wt% Vi. DOWSIL™ CF 9102 from The Dow Chemical Company.

[0113] A-2 [ViMe2SiOi / 2]2[Me2SiO2 / 2]5836 having 0.012 Available under the name

[0114] wt% Vi. XIAMETER™ RBG-0900 Gum from The Dow Chemical Company. A-3 [ViMe2SiOi / 2]2[Me2SiO2 / 2]4829[ViMeSiO2 / 2]25 Available under the name having 0.19 wt% Vi. SILASTIC™ 4-7915 Silicone Gum from The Dow Chemical Company. A-4 [ViMe2SiOi / 2]2[MePhSiO2 / 2]20 having 1.43 Prepare per teachings in US8373286.

[0115] wt% Vi.

[0116] A-5 [ViMe2SiOi / 2]2[Me2Si02 / 2]2io[Ph2Si02 / 2]si Prepare per teachings in US5169920.

[0117] having 0.22 wt% Vi.

[0118] B-l [Me3SiOi / 2]o.34[ ViMe2SiOi / 2]o.11 [Si04 / 2]o.55 Prepare per teachings in US8373286.

[0119] having Mn=5,000; Mw=20,000; 4.1 wt% Vi

[0120] B-2 [Me3SiOi / 2]o.37[ViMe2SiOi / 2]o.o5[Si04 / 2]o.58 Prepare per teachings in US4611042.

[0121] having Mn=5,000; Mw=20,000; 1.6 wt% Vi

[0122] B-3 [Me3SiOi / 2]o.4i[ViMe2SiOi / 2]o.io[Si04 / 2]o.49 Prepare per teachings in US4611042.

[0123] having Mn=3,000; Mw=5,5OO; 3.4 wt% Vi

[0124] C-l [(OH)ViMeSiOi / 2]2[Vi2SiO2 / 2]7.8 having 29.8 Prepare per teachings in US5317072.

[0125] wt% Vi.

[0126] C-2 [ViMeSiO2 / 2]4 cyclic siloxane having 30.3 Prepare per teachings in

[0127] wt% Vi. RO114329B1.

[0128] D-l [HMe2SiOi / 2]2[Ph2SiO2 / 2] with 0.16% SiH Prepare per teachings in US8373286. D-4 A blend of oligomers: Prepare per teachings in US8373286.

[0129] 59 wt% [HMe2SiOi / 2]2[Ph2SiO2 / 2]3,

[0130] 39 wt% [HMe2SiOi / 2]2[Ph2SiO2 / 2]2, and

[0131] 2 wt% [HMe2SiOi / 2]2[Ph2SiO2 / 2], with average

[0132] number of [Ph2SiO2 / 2] units being 2.6 with

[0133] 0.29% SiH.

[0134] D-5 [HMe2SiOi / 2]2[MePhSiO2 / 2] with 0.74% SiH Prepare per teachings in CN103012456

[0135] D-6 [HMe2SiOi / 2]2[MePhSiO2 / 2]4.2 with 0.28% SiH Prepare per teachings in US10155885B2

[0136] D-7 [HMe2SiOi / 2]2[MePhSiO2 / 2]6.4 with 0.2% SiH Prepare per teachings in US10155885B2

[0137] E-l [HMe2SiOi / 2]2[Me2SiO2 / 2]i4 with 0.15% SiH Prepare per teachings in W02003093349 and W02003093369.

[0138] E-2 [HMe2SiOi / 2]60[PhSiO3 / 2]40 with 0.65% SiH Prepare per teachings in US8373286. E-3 [Me3SiOi / 2]2[Me2SiO2 / 2]3.34[HMeSiO2 / 2]5.32 Prepare per teachings in W02003093349 and W02003093369 F-l 40000 ppm platinum-1, 3-diethylenyl-l, 1,3, 3- Available as Pt-47D from Umicore tetramethyldisiloxane complexes

[0139] G-l 1 -ethynyl-1 -cyclohexanol Millipore-Sigma

[0140] H-l Xylene Millipore-Sigma

[0141]

[0142] H-2 Ethylcyclohexane Millipore-SigmaMaking Device Substrate / Carrier Substrate Laminates

[0143] Spin-coat an adhesive composition onto a 5.08 centimeter (cm) (2-inch) silicon wafer (P-type, 525 micrometer thickness, from Silicon Technology Corporation), which serves as a device wafer. Spin-coat at 1500 revolutions per minute (rpm) for 40 seconds to form a coated device wafer. Heat the coated wafer at 100 °C for 2 minutes to remove solvent. Place a carrier wafer (silicone wafer die that is 6 millimeters (mm) by 6 mm and 1 mm thick) onto the adhesive composition coating of the coated device wafer. Place a weight on the carrier wafer so as to apply a 0.2 MPa pressure onto the wafer to compress the carrier wafer onto the adhesive composition and device wafer using an autoclave (SHINDO ENG. Lab., Ltd.). Allow the weight to remain for 5 minutes while heating to 120 °C. Remove the weight and heat the laminated wafers to 190 °C for 10 minutes to cure the adhesive composition. Allow the laminate to cool to 25 °C before evaluating for Adhesion Force and Separation Performance.

[0144] Evaluating Adhesion Force

[0145] Measure adhesion force for the cured adhesive formulation of a device substrate / carrier substrate laminate using a die-shear tester (DAGE4000PLUS BondTester) by applying a shear stress at a rate of 10 millimeters per minute and a shear height at 0.1 millimeters. Desired adhesion force is at least 0.2 N / mm2.

[0146] Evaluating Separation Performance of Laminates

[0147] Separate the device substrate from the carrier substrate of a laminate by inserting a razor blade between the two substrates to begin separation and then peeling the device substrate off from the carrier substrate. Once the wafers are separated, evaluate the surfaces of the wafers for residual adhesive. Rate the separation into one of the following three categories:

[0148] Cohesive Failure (CF) = residual adhesive found on both the carrier wafer and device wafer surfaces. This is undesirable.

[0149] Carrier Wafer (CW) = Separation occurs between the carrier wafer and adhesive so residual adhesive found solely on the device wafer and non on the carrier wafer. This is undesirable.

[0150] Device Wafer (DW) = Separation occurs between the device wafter and adhesive so residual adhesive found solely on the carrier wafer and none on the device wafer. This is the desired outcome.Studies

[0151] 1. Examples of the Invention

[0152] Tables 2, 3, and 4 provide formulations and characterization results for adhesive compositions within scope of the present invention. Ex 1-34 explore use of component (d) with (Ph2SiC>2 / 2)siloxane units. Ex 35-38 explore use of component (d) with (MePhSiC>2 / 2)siloxane units. Notably, hereinbelow “DPh2” is used as an abbreviation for (Ph2SiO2 / 2)siloxane units and “DMePh” is used as an abbreviation for (MePhSiC a) siloxane units.Table 2

[0153] Component I Example

[0154]

[0155] 1 2 [ 3 | 4 5 i 6 7 | 8 \ 9 10 11 | 12 [ 13 14 15 [ 16 | 17 A-l 18.6 17.7 J 17.3 i 16.5 21.9 1 24.5 18.4 17.8 5 16.7 19.9 19.9 | | 19.7 12.7 [ 18.4 i 18.2 A-2 i 19.9 [ • 1 A-3 ■ | [ 19.9

[0156] B-l 69.7 65.0 [ 62.0 61.0 68.0 68.0 66.3 66.9 66.9 69.0 60.0 i 69.0 [ 69.0 70.75 70.75 [ 66.1! 68.7 B-2 9.0 | | •;

[0157] !

[0158] C-l 1.6 1.6! 0.7 i 1.0 D-l 1.4 | 3.8

[0159] D-4 11.5 17.1 i 20.7 i 22.4 8.0 i 3.0 14.7 i 14.7 [ 14.7 11.0 11.0 [ 11.0 [ 11.0 7.9 7.9 i 14.7 [ 8.0 E-2! 0.37 [ i: 7.0 [ i 4.0 E-3 0.5 i 0.5 0.37 [ 1.5 1 •

[0160] F-l (ppm) 50 50 1 50 | 50 50 50 50 i 50 50 50 50 [ 50 i 50 50 50 [ 50 I 50 G-l 0.19 0.19 [ 0.10 0.10 0.11 | 0.11 0.18 0.18 [ 0.18 0.10 0.10 i 0.10 [ 0.10 0.12 0.12! 0.11 | 0.11 H-l 66.6 66.6 i 54.5 i 54.5 64.0 68.0 58.3 [ 63.9 63.9 41.9 41.9 [ 53.0 [ 53.0 62.21 62.21 ( 58.10 1 58.10 Characterization

[0161] () 45[() 44 (5 5 |,) 3()

[0162] SiH / Vi10.31 0.5(5 [ 0.63 [ 0.70 0.34 [ 0.34 0.33 [ 0.30 0.30 0. I< S 0.55 [ 0.39 [ 0.43 (d) / [(d)+(e)] “ 1.0 1.0 \ 1.0 1.6 0.95 [ 0.93 6.98 6.98 | 6.91 [ 1.6 1.6 | 1.6 1.0 1.0 6.53 [ 1.0 [ 0.67 pip

[0163] Ave number of D “ 2.6 2.6 \ 2.6 2.6 2.4 | 1.7 2.6 2.6 2.6 i 2.6 2.6 [ 2.6 2.6 2.6 2.6 [ 2.6 | 2.6 and DMePhin (d)

[0164] wt% Vi(b+c)U14.1 4.1 [ 4.1 | 4.1 4.1 | 4.1 4.1 [ 4.1 | 4.1 [ 4.1 3.8 [ 4.1 4.1 4.7 4.7 [ 4.4 j 4.5 ppm Pt 2 2 i 2 i 2 2! 2 2 i 2 \ 2 \ 2 2 i 2 2 2 2 \ 2 1 2 Homogeneous and Yes Yes \ Yes | Yes Yes j Yes Yes [ Yes [ Yes Yes Yes | Yes Yes Yes Yes [ Yes [ Yes clear?

[0165] Adhesion Strength 0.6 0.6 [ 0.8 | 1.6 0.3 j 0.8 1.2 i 1.() i 2.3 10.7 ON 0.9 1.6 0.6 0.6 [ 0.8 1.2 (N / mm2)

[0166] Separation DW DW [ DW DW DW | DW DW [ DW [ DW DW DW I DW DW DW DW [ DW [ DW

[0167]

[0168] Performance1V

[0169] 1this is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.

[0170] IIThis is wt%(d) divided by sum of tire wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0.

[0171] IIIthis is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The value needs to be in a range of 3.5 to 10.0

[0172] ivCF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer. DW is desired.Ta Table 3

[0173] Component Example

[0174] 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | 34 A-l 16.7 14.2 14.5 13.7 20.4 | 15.4 15.0 8.4 8.4 15.9 8.7 7.7 6.7 i 14.9 A-2 I 18.4 17.6 16.5

[0175] B-l 59.9 63.7 65.1 J 61.6 67.0 | 68.5 69.3 61.4

[0176] B-2 69.1 67.4 69.0 59.0 59.0

[0177] B-3 1 78.1 69.1 59.9 67.1 C-l 3.3 1.0 1.0 1.0 5.0 7.7 7.5 7.5 7.5 4.3 7.7 6.7 7.5 C-2 3.5 1.5 1.4 I 7.0

[0178] D-4 20.0 18.4 18.8 i 17.8 11.0 I 12.0 10.0 10.0 7.7 7.5 15.0 25.0 18.0 8.7 15.4 26.7 I 7.5 E-2 i 5.5 I 2.0 7.0 2.5 | 3.0 E-3 0.5 i

[0179] F-l (ppm) 50 50 50 i 50 50 50 50 50 50 50 50 50 50 50 50 50 | 50 G-l 0.10 0.11 0.11 i 0.11 0.11 | 0.11 0.11 0.11 0.12 0.11 0.11 0.11 0.11 0.12 0.10 0.10 0.10 H-l 52.7 44.2 44.2 44.2 55.0 55.0 55.0 55.0 43.2 42.1 42.1 42.1 42.1 64.0 56.6 49.0 i 41.9 Characterization

[0180] SiH / Vi10.45 0.39 0.47 0.80 0.31 | 0.30 0.36 0.50 0.17 0.30 0.33 0.59 0.43 0.17 0.26 0.52 | 0.25 (d) / [(d)+(e)]u1.00 1.00 1.00 0.76 0.96 1.00 0.83 0.59 1.00 0.75 1.00 1.00 1.00 1.00 1.00 1.00 0.71 Ave number of DPh22.6 2.6 2.6 | 2.6 2.6 | 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 | 2.6 and DMePhin (d)

[0181] wt% Vi.b+o1" 5.4 5.5 4.7 | 4.7 4.5 4.5 4.5 6.0 4.7 4.7 4.6 5.0 4.9 4.8 6.0 6.0 6.0 ppm Pt 2 2 2 i 2 2 i 2 2 2 2 2 2 2 2 2 2 2 | 2 Homogeneous and Yes Yes Yes | Yes Yes | Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes | Yes clear?

[0182] Adhesion Strength 0.8 1.4 1.3 1.3 1.3 | 1.3 1.3 2.6 0.9 1.0 1.4 1.8 1.0 0.3 0.8 0.8 1.0 (N / mm2)

[0183] Separation DW DW DW | DW DW | DW DW DW DW DW DW DW DW DW DW DW | DW

[0184]

[0185] Performancelv

[0186] Ithis is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.

[0187] IIThis is wt%(d) divided by sum of the wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0.

[0188] IIIthis is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c).

[0189] The value needs to be in a range of 3.5 to 10.0

[0190] IVCF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer. DW is desired.Table 4

[0191] Component Example

[0192] 35 36 37 38

[0193] A-l 21.3

[0194] A-2 19.5 19.0 22.4

[0195] B-l 67.6 69.4 69.4 62.5

[0196] D-6 11.0 11.0 11.0

[0197] D-7 15.0

[0198] E-2 0.5

[0199] F-l (ppm) 50 50 50 50

[0200] G-l 0.10 0.10 0.10 0.10

[0201] H-2 78.6 72.4 72.4 63.9

[0202] Characterization

[0203] SiH / C=C10.30 0.29 0.32 0.32

[0204] (d) / [(d)+(e)] “ 1.00 1.00 0.96 1.00

[0205] Ave number of D Ph2 and 4.2 4.2 4.2 6.4

[0206] DMePhin (d)

[0207] wt% Vi(b+c)ln4.1 4.1 4.1 4.1

[0208] ppm Pt 2 2 2 2

[0209] Homogeneous and clear? Yes Yes Yes Yes

[0210] Adhesion Strength i'N / mm‘) 0.9 0.2 0.2 0.8

[0211]

[0212] Separation Performance1VDW DW DW DW

[0213] Ithis is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.

[0214] IIThis is wt%(d) divided by sum of the wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0.

[0215] IIIthis is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The value needs to be in a range of 3.5 to 10.0

[0216] IVCF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer

[0217] 2. Exploring Component (d)

[0218] Table 5 provides comparative example formulations that explore component (d) variations. Comparative Examples (CEs) A-E explores use of an alternative to component (d) that only contains a single DPh2siloxane unit and reveals that component (d) must have more than one DPh2siloxane unit or adhesive does not cleanly separate from the device wafer. CEs GG and HH explore use of DMePhinstead of DPh2but with only 1.00 DMePhper molecule and similarly show more than one is necessary or adhesive does not cleanly separate from the device wafer. CEs F-K explore use of a similar siloxane to component (d) but without the DPh2siloxane unit and reveals that the DPh2siloxane units are necessary to achieve clean adhesive separation from the device wafer. Notably, CE D also is an illustration of what happens when the SiH / C=C ratio is too high and the weight of vinyl groups from components (b) and (c) relative to weight of (b) and (c) is out of scope.Table 5

[0219] i Component Comparative Example

[0220] A B c D E F G H | I | J K GG HH i A-l 20.0 19.2 18.5 15.9 7.7 15.2 11.3 19.4 i 17.2! 21.4 18.1 | 30.8 24.8 i B-l 71.8 69.1 66.5 56.0 44.0 72.0 i 67.0 71.0 68.0 i 64.1 64.1 i B-2 71.3! i!

[0221] B-3 69.1!

[0222] | C-l 1.6 7.7

[0223] 1 D-l 8.0 11.5 14.8 11.1 15.4 15.4

[0224] i D-5 | 5.0 11.0 I E-l 28.6 44.5 •

[0225] i E-2 8.45 i 15.6!

[0226] i E-3 | | 7.38 13.7 i

[0227] i F-l (ppm) 50 50 50 50 50 50 50 50 i 50! 50 50 i 50 50 i G-l 0.20 0.19 0.18 0.1 0.1 0.19 0.19 0.19 i 0.19 0.19 0.19 | 0.10 0.10 i H-l 63.2 60.7 58.5 44.6 56.6 60.7 60.7 60.7 60.7 i 60.7 60.7 |

[0228] | H-2; i 1 58.7 61.3 i Characterization

[0229] i SiH / Vi * 0.44 0.67 0.89 1.00 0.55 0.50 0.99 0.50 0.99! 0.44 0.86 i 0.38 0.83 i (d) / [(d)+(e)] “ 1.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 i 0.00 0.00 0.00 | 1.00 1.00: DPh2

[0230] I Ave number of D and 1.0 1.0 1.0 1.0 1.0 0 0 0 0 0 0 | 1.0 1.0 | DMePhin (d)

[0231] | wt% Vi(b+c)"' 4.1 4.1 4.1 2.5 6.0 4.1 4.1 4.1 i 4.1 4.1 4.1 | 4.1 4.1 i ppm Pt 2 2 2 2 2 2 2 2 i 2 2 2 1 2 2 1 Homogeneous and clear? Yes Yes Yes Yes Yes Yes Yes Yes i Yes Yes Yes | Yes Yes i Adhesion Strength (N / mm2) 2.4 1.1 1.5 6.2 0.8 1.3 0.9 1.0 | 1.2 1.2 1.2 | 2.2 4.2

[0232]

[0233] i Separation PerformanceivCW CW CW CF CW CF CW CW CW i CW CW i CF CW this is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.IIThis is wt%(d) divided by sum of the wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0.

[0234] IIIThis is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The value needs to be in a range of 3.5 to 10.0

[0235] ivCF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer3. Exploring SiH / Vi Ratio

[0236] Table 6 provides comparative example formulations that explore SiH / Vi ratio in the adhesive composition. CEs L-R data in the table reveals that when the SiH / Vi ratio is either below 0.15 or is 1.0 or greater than the adhesive does not cleanly separate from the device wafer.

[0237] CEs O and P also highlight that without component (d) present, but with an aryl-functional component (b) instead, the formulation is not homogeneous and fails to be able to be evaluated as an adhesive.

[0238] CEs N, Q and D also highlight formulations where the weight of vinyl groups from components (b) and (c) relative to weight of (b) and (c) is out of scope.

[0239] Table 6

[0240] Component Comparative Example

[0241] L M N 0 P Q R D A-l 23.0 14.6 17.6 23.1 23.1 15.9 A-4 30.9

[0242] A-5 31.0

[0243] B-l 71.9 56.0 69.0 69.0

[0244] B-2 66.0 69.1 71.3 B-3 69.1 C-l 3.8 3.8 1.6 D-4 5.0 29.3 16.2 3.8 3.8

[0245] D-l 11.1 F-l (ppm) 50 50 50 50 50 50 50 50 G-l 0.12 0.10 0.19 0.12 0.12 0.12 0.12 0.1 H-l 63.2 54.5 55.7 63.2 63.2 68.8 68.8 44.6 Characterization

[0246] SiH / Vi10.13 1.00 1.00 0.00 0.00 0.12 0.09 1.00 (d) / [(d)+(e)] “ 1.00 1.00 1.00 — — 1.00 1.00 1.00 Ave number of DPh2and DMePhin (d) 2.6 2.6 2.6 0 0 2.6 2.6 1.0 wt% Vi(b+c)ul4.1 4.1 1.9 4.1 4.1 3.4 4.8 2.5 ppm Pt 2 2 2 2 2 2 2 2 Homogeneous and clear? Yes Yes Yes No No Yes Yes Yes Adhesion Strength (N / mm2) 1.1 0.8 3.5 __ v __ V 2.8 1.2 6.2

[0247]

[0248] Separation Performance1VCF / CW CW CW __ v _ V CW CF CFIthis is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.

[0249] IIThis is wt% (d) divided by sum of the wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0.

[0250] IIIthis is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The value needs to be in a range of 3.5 to 10.0

[0251] IVCF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer. DW is desired.

[0252] vCould not be measured.4. Exploring Vi(b)+(c) / [(b)+(c)]

[0253] Table 7provides comparative example formulations that explore ratio of the weight of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The data shows that when this ratio is below 3.5 then the adhesive does not cleanly separate from the device wafer.

[0254] CEs N, Q and D also represent formulations where the Si / C=C ratio is out of scope. CE D further represents a formulation where the number of DP112groups is too low.

[0255] Table 7

[0256] Component Comparative Example

[0257] S T u V w X Y N Q D A-l 19.9 19.9 19.9 19.0 17.9 15.4 8.3 17.6 23.1 15.9 B-l 40.0 20.0

[0258] B-2 29.0 49.0 69.0 72.0 70.0 66.0 69.1 71.3 B-3 69.1 74.8

[0259] C-l 3.8 1.6 D-l 11.1 D-4 11.0 11.0 11.0 8.8 11.9 15.4 16.7 16.2 3.8

[0260] F-l (ppm) 50 50 50 50 50 50 50 50 50 50 G-l 0.10 0.10 0.10 0.19 0.19 0.10 0.10 0.19 0.12 0.10 H-l 41.9 41.9 41.9 55.7 55.7 56.6 56.6 55.7 68.8 44.6 Characterization

[0261] SiH / Vi ‘ 0.39 0.49 0.65 0.50 0.69 0.51 0.51 1.00 0.12 1.00 (d) / [(d)+(e)l “ 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Ave number of D Ph 2 and 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 1.0 DMePhin (d)

[0262] Wt% Vi(b+C)"’ 3.2 2.5 1.9 1.9 1.9 3.4 3.4 1.9 3.4 2.5 ppm Pt 2 2 2 2 2 2 2 2 2 2 Homogeneous and clear? NM* NM* Yes Yes Yes Yes Yes Yes Yes Yes Adhesion Strength 0.8 1.0 2.9 1.8 0.9 3.1 2.3 3.5 2.8 6.2 (N / mm2)

[0263]

[0264] Separation PerformanceIVcw CW CW CW CW CF CF CW CW CF1this is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.

[0265] “ This is wt% (d) divided by sum of the wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0.

[0266] this is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The value needs to be in a range of 3.5 to 10.0

[0267] lvCF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer. DW is desired.

[0268] * Not measured5. Exploring Aryl on Component (a)

[0269] Table 8 provides comparative example formulations that explore having aryl functionality on the component (a) siloxane. Data in the table reveals that aryl groups on the (a) component results in undesirably inhomogeneous formulations.

[0270] Table 8

[0271] Component Comparative Example

[0272] O p z AA

[0273] A-4 30.9 19.9

[0274] A-5 31.0 20.0

[0275] B-l 69.0 69.0 69.0 69.0

[0276] D-4 11.0 11.0

[0277] F-l (ppm) 50 50 50 50

[0278] G-l 0.12 0.12 0.12 0.1

[0279] H-l 63.2 63.2 63.2 63.2 Characterization

[0280] SiH / Vij0.00 0.00 0.28 0.30

[0281] (d) / [(d)+(e)] « — — 1.00 1.00

[0282] Ave number of DPh2and DMePhin (d) N / A N / A 2.6 2.6

[0283] wt% Vi(b+c) 4.1 4.1 4.1 4.1

[0284] ppm Pt 2 2 2 2

[0285] Homogeneous and clear? NO NO NO NO

[0286] Adhesion Strength (N / mm2) __ V

[0287]

[0288] Separation Performanceiv

[0289] Ithis is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.

[0290] IIThis is wt% (d) divided by sum of the wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0. III this is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The value needs to be in a range of 3.5 to 10.0 IV CF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer. DW is desired.

[0291] vCould not be measured.

[0292] 6. Exploring (d) / [(d)+(e)] and Concentration of Component (b)

[0293] Table 9 provides comparative example formulations exploring the ratio of the wt% of component (d) relative to the sum of the wt% values for component (d) and (e).

[0294] CEs BB and CC show that when the wt% (d) / [sum of wt%(d)+(e)] is below 0.50, then adhesive does not cleanly separate from the device wafer.

[0295] CEs DD and EE show that when the concentration of component (b) is below 57 wt% or above 75 wt% then the adhesive cannot perform properly. Below 57 wt% (b) results in insufficient curing of the adhesive composition. Above 75 wt% results in cracking of the cured adhesive composition.Table 9

[0296] Component Comparative Example

[0297] BB CC DD EE

[0298] A-l 13.9 13.4 33.4 8.4

[0299] B-l 55.0 80.0

[0300] B-2 62.4

[0301] B-3 60.1

[0302] C-l 6.9 6.7

[0303] D-l

[0304] D-4 6.9 6.7 11.5 11.5

[0305] E-2 9.8 13.0

[0306] F-l (ppm) 50 50 50 50

[0307] G-l 0.10 0.10 0.12 0.12

[0308] H-l 39.0 37.6 63.2 63.2 Characterization

[0309] SiH / Vi * 0.70 0.70 0.40 0.27 (d) / [(d)+(e)] ” 0.41 0.34 1.00 1.00

[0310] Ave number of DPh2and DMePhin (d) 2.6 2.6 2.6 2.6

[0311] wt% Vi(b+c)iii4.7 6.0 4.1 4.1

[0312] ppm Pt 2 2 2 2 Homogeneous and clear? Yes Yes Yes Yes

[0313] Adhesion Strength (N / mm2) 2.1 2.3

[0314]

[0315] Separation PerformanceivCF CW

[0316] Ithis is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.

[0317] IIThis is wt% (d) divided by sum of the wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0.

[0318] IIIthis is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The value needs to be in a range of 3.5 to 10.0

[0319] IVCF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer. DW is desired.

[0320] vCould not be measured.

[0321] 7. Exploring Average Number of DPh2and DMePhunits in Component (d)

[0322] Table 10 provides comparative example formulation exploring what happens when the average number of DPh2and DMePhsiloxane units in component (d) is below 1.5.

[0323] CEs A, B, C, and FF show that when the average number of DPh2siloxane units in component (d) is below 1.5, then the adhesive does not cleanly separate from the device wafer. Similarly, CEs GG and HH show that when the average number of DMePhsiloxane units in component (d) is below 1.5, then the adhesive does not cleanly separate from the device wafer.Table 10

[0324] Component Comparative Example

[0325] A B C FF GG HH

[0326] A-l 20.0 19.2 18.5 25.6 30.8 24.8 B-l 71.8 69.1 66.5 68.0 64.1 64.1 D-l 8.0 11.5 14.8 4.81

[0327] D-4 1.0

[0328] D-5 5.0 11.0 F-l (ppm) 50 50 50 50 50 50 G-l 0.20 0.19 0.18 0.11 0.10 0.10 H-1 63.2 60.7 58.5 71.0

[0329] H-2 58.7 61.3 Characterization

[0330] SiH / Vi!0.44 0.67 0.89 0.34 0.38 0.83 (d) / [(d)+(e)] “ 1.00 1.00 1.00 0.92 1.00 1.00 Ave number of DPh2and DMePhin (d) 1.0 1.0 1.0 1.3 1.0 1.0 wt% Vi(b+c)ul4.1 4.1 4.1 4.1 4.1 4.1 ppm Pt 2 2 2 2 2 2 Homogeneous and clear? Yes Yes Yes Yes Yes Yes Adhesion Strength (N / mm2) 2.4 1.1 1.5 2.0 2.2 4.2

[0331]

[0332] Separation Performance1VCW CW CW CW CF CW1this is the molar ratio of SiH groups to vinyl groups in the adhesive composition. Needs to be in a range of 0.15 to less than 1.0.

[0333] IIThis is wt% (d) divided by sum of the wt% values for components (d) and (e). Needs to be in a range of 0.5 to 1.0. III this is a wt% of vinyl groups from components (b) and (c) relative to combined weight of components (b) and (c). The value needs to be in a range of 3.5 to 10.0 IV CF=Cohesive Failure. DW=Device Wafer. CW=Carrier Wafer. DW is desired.

Claims

CLAIMS:

1. An adhesive composition comprising the following components:(a) 5 to 30 weight-percent of a linear terminal alkenyl-functional siloxane comprising (R^SiOi / ) and (R1R2SiO2 / 2) siloxane units and that contains 0.01 to 1.0 weight-percent vinyl groups based on molecular weight of the linear temrinal alkenyl-functional siloxane and that is free of silicon-bound aryl functionality;(b) 57 to 75 weight-percent of an alkenyl-functional siloxane resin comprising (R^SiOi / i), (R12R2SiOi / 2) and (SiC>4 / 2) siloxane units;(c) 0 to 10 weight-percent of a poly siloxane comprising (R1R2SiC>2 / 2) siloxane units, that is free of (R^SiC^) siloxane units, and that contains 27 to 31 weight-percent vinyl groups based on molecular weight of the polysiloxane; (d) 2.5 to 30 weight-percent of a linear silicone oligomer component that comprises one or more than one linear silicone oligomer that have (Ph2SiO2 / 2) and / or (MePhSiO2 / 2) siloxane units, provided that the average number of (Ph2SiO2 / 2) and (MePhSiO2 / 2) siloxane units per oligomer molecule in the linear silicone oligomer component is 1.5 or more and the linear silicone oligomer component has an average of two or more silicon-bound hydrogen atoms per molecule, where Ph refers to a phenyl group and Me refers to a methyl group;(e) optionally, an additional siloxane crosslinker outside the composition scope of component (d) and that contains two or more silicon-bound hydrogen atoms per molecule, where the weight-percent of component (e) is such that the wt% of component (d) divided by the sum of the weight-percent values for components (d)+(e) has a value in a range of 0.5 to 1.0;(f) 0.5 to 100 weight parts per million weight parts of adhesive composition of the platinum-group metal of a hydrosilylation catalyst;(g) 5 to 10,000 weight parts per million weight part of adhesive composition of a hydrosilylation inhibitor; and(h) 1 to 200 weight-percent solvent;where:(i) weight-percent values are relative to the combined weight of components (a)-(g) unless otherwise stated;(ii) R1refers to C1-C10 alkyl groups and R2refers to C2-C10 alkenyl groups with terminal carbon-carbon double bonds;(iii) the adhesive composition has a SiH / Vi molar ratio in a range of 0.15 to less than 1.0; and(iv) the weight-percent of vinyl groups from components (b) and (c) relative to the combined weight of components (b) and (c) is in a range of 3.5 to 10.0.

2. The adhesive composition of claim 1, wherein component (a) is selected from organosiloxanes having an average chemical formula (I):(R12R2SiOi / 2)2(R12SiO2 / 2)d(R1R2SiO2 / 2)d’ (I) where: R1independently in each occurrence is selected from C1-C10 alkyl groups and R2independently in each occurrence is selected from C2-C10 alkenyl groups with terminal carbon-carbon double bonds; subscript d has a value in a range of 1000 to 8000, and d’ has a value in a range of 0 to 50.

3. The adhesive composition of claim 1 or claim 2, wherein component (b) is selected from those having an average chemical formula (II):(R13SiOi / 2)m(R12R2SiOi / 2)m’(SiO4 / 2)q(II) where R1independently in each occurrence is selected from C4-C10 alkyl groups and R2independently in each occurrence is selected from C2-C10 alkenyl groups with terminal carbon-carbon double bonds; subscript m has a value in a range of 0.25 to 0.50; subscript m’ has a value in a range of 0.02 to 0.20; and subscript q has a value in a range of 0.45 to 0.60, where the sum of m+m’+q equals 1.00.

4. The adhesive composition of any one previous claim, wherein component (c) is selected from [R1R2SiO2 / 2]4and siloxanes having an average chemical formula (III):(R1R2(OZ)SiOi / 2)2(R1R2SiO2 / 2)d' (III) where: Z refers to a hydrogen or hydrocarbyl; R1independently in each occurrence is selected from C1-C10 alkyl groups and R2independently in each occurrence is selected from C2-C10 alkenyl groups with terminal carbon-carbon double bonds;“OZ” in each occurrence is selected from -OH and -OR1groups; and subscript d’ has a value in a range of 3 to 20.

5. The adhesive composition of any one previous claim, wherein component (d) is one or more than one oligomer selected from those with average chemical formula (IV):(HR12SiOi / 2)2(Ph2SiO2 / 2)d"((CH3)PhSiO2 / 2)d"' (IV) where: R1independently in each occurrence is selected from Ci-Cio alkyl groups, “Ph” refers to a phenyl group and subscript d” has a value in a range of zero to 10, d’” has a value in a range of zero to 10, provided that that sum of d” and d’” is in a range of 1 to 10.

6. The adhesive composition of any one previous claim, wherein the adhesive composition is free of epoxy-modified polyorganosiloxane.

7. The adhesive composition of any one previous claim, wherein the adhesive composition is free of non-functional organopolysiloxanes.

8. A process for using the adhesive composition of any one of the previous claims, the process comprising the following steps:(a) coating the adhesive composition onto a device substrate to form a coated device substrate;(b) heating the coated device substrate to remove solvents from the adhesive composition to form a dried adhesive composition on the coated device substrate;(c) placing a carrier substrate in contact with the dried adhesive composition to form a laminate comprising the device substrate, dried adhesive composition, and carrier substrate;(d) heating the laminate to cure the dried adhesive composition between the carrier substrate and device substrate;(e) optionally, subjecting the laminated article to a process for modifying the device substrate; and(f) separating the device substrate from the carrier substrate.

9. The process of claim 8, wherein the only adhesive between the device substrate and the carrier substrate is the single adhesive composition of any one of the previous claims.

10. The process of claim 8 or 9, wherein separating the device substrate from the carrier substrate occurs at a temperature in a range of 23 to 27 degrees Celsius.

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