A thermosetting silicone resin with low volatility and adsorption for LEDs

Abstract

The present invention provides a low-volatile adsorption thermosetting silicone resin for LEDs. The raw materials for the low-volatile adsorption thermosetting silicone resin for LEDs include the following components: a vinyl silicone resin, a hydrogen-containing crosslinking agent, a tackifier, a thixotropic agent, an inhibitor, and a catalyst. The present invention develops the low-volatile adsorption thermosetting silicone resin by structurally designing the hydrogen-containing resin / silicone oil to reduce volatile components during the curing process. This reduces the formation of contaminants on the gold electrode pads of semiconductor chips during the curing process of the resin composition, avoiding adverse effects on the subsequent wire bonding process and thus reducing production costs.

Description

Technical Field

[0001] The invention belongs to the technical field of interface adhesive material preparation, and particularly relates to a low-volatile adsorption thermosetting silicone resin for LEDs. Background Art

[0002] Compared with previous light-emitting devices such as light bulbs or fluorescent lamps, optical semiconductors (LEDs) have become rapidly popular in recent years due to their advantages of low energy consumption and long life. When making an optical semiconductor device, a curable resin composition called a chip mounting material is first applied to a specified position on the optical semiconductor substrate. The purpose of this composition is to fix the optical semiconductor chip on the substrate. However, it has been reported that due to factors such as the addition-curing silicone resin used, the type of optical semiconductor chip, or the curing conditions of the resin composition, contaminants are formed on the gold electrode pads of the semiconductor chip when the resin composition is cured. The contaminants are mainly attributed to the low molecular weight siloxanes contained in the addition-curing silicone resin, especially hydrogen atoms bonded to silicon atoms. When contaminants are present in the electrode pads, the subsequent wire bonding process will be adversely affected, resulting in waste of production materials. Summary of the Invention

[0003] To address the problem of silicone resin contamination of semiconductor chips, the present invention employs a structural design of hydrogen-containing resin / silicone oil to reduce volatile components during the curing process, thereby developing a low-volatile adsorption thermosetting silicone resin. This reduces the formation of contaminants on the gold electrode pads of semiconductor chips during the curing process of the resin composition, thus avoiding adverse effects on the subsequent wire bonding process and reducing production costs.

[0004] The present invention provides a low-volatile adsorption thermosetting silicone resin for LEDs, the raw materials of which, in parts by mass, include the following components:

[0005] Vinyl silicone resin 40-80%

[0006]

[0007] The vinyl silicone resin is a vinyl silicone resin with a branched network structure;

[0008] The hydrogen-containing cross-linking agent is a hydrogen-based silicone resin with a branched network structure;

[0009] The tackifier is a boron- and epoxy-containing organosilicon tackifier, model IOTA 3950-18, code Z;

[0010] The thixotropic agent is fumed silica surface treated with octamethylcyclotetrasiloxane, with a specific surface area of ​​300-500m 2 / g;

[0011] The inhibitor is an alkynol inhibitor, preferably one or more of methylbutynol, 3, 7, 11-trimethyldodecene-3-ol, 2-vinyl isopropanol, 2-ethynylbutan-2-ol, 3-phenyl-1-butene-3-ol, and 1-ethynyl-1-cyclohexanol;

[0012] The catalyst is a Karstedt platinum catalyst with a platinum content of 5000 ppm;

[0013] Preparation of the vinyl silicone resin: different numbers of methoxy / ethoxy siloxy monomers and vinyl end-capping agents are synthesized by hydrolysis and condensation method; the raw materials for synthesizing the vinyl silicone resin include the following components, calculated by weight:

[0014] Trifunctional siloxane 150-200,

[0015] Difunctional siloxane 20-50,

[0016] Vinyl blocking agent 5-40,

[0017] The trifunctional siloxane is selected from phenyltrimethoxysilane, phenyltrichlorosilane, phenyltriethoxysilane, methyltrimethoxysilane, methyltrioxyethylsilane or methyltrichlorosilane.

[0018] The difunctional siloxane is selected from methylvinyldimethoxysilane, phenylvinyldimethoxysilane, methylvinyldiethoxysilane, phenylvinyldiethoxysilane, diphenyldimethoxysilane or divinyldimethoxysilane, diphenyldiethoxysilane.

[0019] The vinyl end-capping agent is selected from tetramethyldivinyldisiloxane and hexavinyldisiloxane.

[0020] Preparation of the hydrogen-containing crosslinking agent: different numbers of methoxy / ethoxysilyloxy monomers and hydrogen-containing end-capping agents are synthesized by hydrolysis and polycondensation; the hydrogen-containing crosslinking agent is synthesized in parts by mass:

[0021] Tetrafunctional siloxane 0-120,

[0022] Trifunctional siloxane 80-200,

[0023] Hydrogen-containing capping agent 40-80,

[0024] The tetrafunctional siloxane is selected from methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate or butyl orthosilicate.

[0025] The trifunctional siloxane is selected from phenyltrimethoxysilane, phenyltrichlorosilane, phenyltriethoxysilane, methyltrimethoxysilane, methyltrioxyethylsilane or methyltrichlorosilane.

[0026] The hydrogen-containing end-capping agent is selected from tetramethyldihydrogendisiloxane, tetrahydrogendimethyldisiloxane, and tetraphenyldihydrogendisiloxane.

[0027] Preparation of the low-volatile adsorption thermosetting silicone resin for LED:

[0028] (1) Weighing vinyl silicone resin and hydrogen-containing crosslinking agent by weight;

[0029] (2) Mix well at 100°C and cool to room temperature for later use;

[0030] (3) adding a thickener and an inhibitor to the raw materials mixed uniformly in (2) and mixing them uniformly again;

[0031] (4) adding the raw materials mixed uniformly in (3) to the catalyst and thixotropic agent and mixing uniformly;

[0032] (5) The organic silicone resin mixed evenly in (4) is subjected to post-treatment such as filtration and degassing to obtain the low-volatile adsorption thermosetting organic silicone resin for LED

[0033] The low-volatile adsorption thermosetting silicone resin for LED is used to bond the light-emitting chip and the silver-plated layer of the bracket in the white light LED field: the chip is bonded to the fixed position of the bracket using silicone resin through a crystal bonding machine, and then placed in a 160°C oven for 3 hours to complete curing, and then subsequent processes such as wire bonding and packaging are carried out.

[0034] The low-volatile adsorption thermosetting silicone resin for LEDs of the present invention has the following beneficial effects:

[0035] 1. Through the optimization of molecular structure design, component ratio and synthesis process, a hydrogen-containing crosslinking agent with a specific molecular weight was synthesized;

[0036] 2. Through formula optimization, the volatile matter generated by the resin composition during curing is greatly reduced

[0037] The low-volatile adsorption thermosetting silicone resin for LED of the present invention is placed in a 160° C. oven and baked for 3 hours. The volatile content is measured to be 0.11%, and the possibility of chip electrodes being contaminated is reduced to 20%. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 : Adsorption test comparison chart. DETAILED DESCRIPTION

[0039] (1) Synthesis of vinyl silicone resin

[0040] The preparation of vinyl silicone resin includes the following steps: weighing the raw materials in the table below by weight and placing them in a reaction vessel; stirring for 5 minutes, adding a pre-prepared acid aqueous solution (10 parts of hydrochloric acid corresponds to 150 parts of deionized water), then placing it in an oil bath, heating it at 50°C and stirring it for 5 hours, washing it with water until it is neutral after the reaction, then adding 1 part of potassium hydroxide, heating it to 85°C, stirring it for 6 hours, and washing it with water until it is neutral after the reaction, and then removing the precipitate to obtain a clear and transparent vinyl silicone resin.

[0041] Table 1 Raw materials and proportions of vinyl-containing silicone resins

[0042]

[0043]

[0044] (2) Synthesis of hydrogen-containing crosslinking agent

[0045] The preparation of the hydrogen-containing crosslinking agent includes the following steps: weighing the raw materials in the table below by weight and placing them in a reaction vessel; stirring for 5 minutes, adding a pre-prepared acid aqueous solution (60 parts of hydrochloric acid corresponding to 100 parts of deionized water), then placing the mixture in an oil bath, heating at 70°C and stirring for 5 hours, washing with water until neutral after the reaction, then adding 0.5 parts of trifluoromethanesulfonic acid, heating to 110°C, stirring for 6.5 hours, and washing with water until neutral after the reaction, and then removing the residue to obtain a clear and transparent hydrogen-containing crosslinking agent.

[0046] Table 2 Raw materials and proportions of hydrogen-containing crosslinking agents

[0047]

[0048] (III) Example: Preparation of the low-volatile adsorption silicone resin for LEDs, comprising the following steps:

[0049] (1) Weighing raw materials by weight, the raw materials including vinyl silicone resin and hydrogen-containing crosslinking agent;

[0050] (2) Mix well at 100°C and cool to room temperature for later use;

[0051] (3) adding a thickener and an inhibitor to the raw materials mixed uniformly in (2) and mixing them uniformly again;

[0052] (4) adding the catalyst and thixotropic agent to the raw materials mixed uniformly in (3) and mixing uniformly;

[0053] (5) The organic silicone resin mixed evenly in (4) is subjected to post-treatment such as filtration and degassing to obtain the low-volatile adsorption thermosetting organic silicone resin for LED

[0054] See Table 3 for raw materials

[0055]

[0056] See Table 4 for the raw material usage table

[0057] Vinyl silicone resin Hydrogen-containing crosslinking agent Tackifier Thixotropic agent inhibitors catalyst Example 1 10.002 7.202 0.703 0.501 0.014 0.027 Example 2 9.997 6.750 0.552 0.450 0.015 0.028 Example 3 10.003 6.540 0.504 0.552 0.016 0.027 Example 4 10.001 6.503 0.451 0.552 0.017 0.026 Example 5 9.998 6.752 0.501 0.502 0.015 0.027 Example 6 10.001 6.004 0.453 0.451 0.016 0.027 Example 7 10.000 6.003 0.550 0.483 0.015 0.028 Example 8 9.999 6.502 0.407 0.503 0.015 0.029 Example 9 10.003 6.401 0.551 0.501 0.014 0.027 Comparative Example 10 9.999 7.003 0.500 0.470 0.015 0.028 Comparative Example 11 10.002 6.803 0.503 0.490 0.015 0.027 Comparative Example 12 10.001 6.601 0.440 0.502 0.015 0.027

[0058] (6) Test examples

[0059] Volatile matter test:

[0060] Weigh 3g of the silicone resin obtained in the example accurately and place it in a clean 5ml beaker. Record the actual weight. Bake it in a 160℃ oven for 3h. After cooling to room temperature, take it out and weigh the weight loss to calculate the volatile matter. The results are shown in the table below.

[0061] Volatile matter (%) Example 1 0.22 Example 2 0.15 Example 3 0.22 Example 4 0.27 Example 5 0.20 Example 6 0.20 Example 7 0.12 Example 8 0.11 Example 9 0.10 Comparative Example 10 0.44 Comparative Example 11 0.48 Comparative Example 12 0.45

[0062] Adsorption test:

[0063] (1) The organic silicone resin obtained in the example and the control sample were respectively solidified by a solidification machine, and then the solidification bracket was placed horizontally in a beaker with the front side facing up, and an aluminum foil of appropriate size was placed under the bracket. 1.000g of the corresponding organic silicone resin was coated on the surface of the aluminum foil;

[0064] (2) Seal the beaker with aluminum foil and bake in an oven at 160°C for 3 hours;

[0065] (3) After baking, return to room temperature and take out the bracket from the beaker. Observe the adsorption under a microscope. The results are shown in the attached figure:

[0066] As can be seen from the figure, the chip electrodes in the control example are clearly contaminated, appearing golden yellow, while the electrodes in the examples are mostly in their original color, uncontaminated by volatiles. In Example 2, the electrodes exhibit a few golden spots. This indicates that the greater the volatile content of the silicone resin composition, the greater the degree of chip electrode contamination.

Claims

1. A low-volatile adsorption thermosetting silicone resin for LED, characterized in that: The raw materials include the following components in parts by mass: Vinyl silicone resin 40~80% Hydrogen-containing crosslinking agent 20~50% Thickener 1~6% Thixotropic agent 1~5% Inhibitor 0.1~2% Catalyst 0.1~2% The vinyl silicone resin is a vinyl silicone resin with a branched network structure; The hydrogen-containing cross-linking agent is a hydrogen-based silicone resin with a branched network structure; The tackifier is a boron- and epoxy-containing organosilicon tackifier; The thixotropic agent is fumed silica surface treated with octamethylcyclotetrasiloxane, with a specific surface area of ​​300-500m 2 / g; The inhibitor is an alkynol inhibitor, selected from one or more of methylbutynol, 3, 7, 11-trimethyldodecene-3-ol, 2-vinyl isopropanol, 2-ethynylbutan-2-ol, 3-phenyl-1-butene-3-ol, and 1-ethynyl-1-cyclohexanol; The catalyst is a Karstedt platinum catalyst with a platinum content of 5000 ppm; Preparation of the hydrogen-containing crosslinking agent: different numbers of methoxy / ethoxysilyloxy monomers and hydrogen-containing end-capping agents are synthesized by hydrolysis and polycondensation; the hydrogen-containing crosslinking agent is synthesized in parts by mass: Tetrafunctional siloxane 80-120, Trifunctional siloxane 80-200, Hydrogen-containing capping agent 40-80, The tetrafunctional siloxane is selected from methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate or butyl orthosilicate; The trifunctional siloxane is selected from phenyltrimethoxysilane, phenyltrichlorosilane, phenyltriethoxysilane, methyltrimethoxysilane, methyltrioxyethylsilane or methyltrichlorosilane; The hydrogen-containing end-capping agent is selected from tetramethyldihydrogendisiloxane, tetrahydrogendimethyldisiloxane, and tetraphenyldihydrogendisiloxane; Preparation of the vinyl silicone resin: different numbers of methoxy / ethoxy siloxy monomers and vinyl end-capping agents are synthesized by hydrolysis and condensation method; the raw materials for synthesizing the vinyl silicone resin include the following components, calculated by weight: Trifunctional siloxane 150-200, Difunctional siloxane 20-50, Vinyl blocking agent 5-40; The trifunctional siloxane is selected from phenyltrimethoxysilane, phenyltrichlorosilane, phenyltriethoxysilane, methyltrimethoxysilane, methyltrioxyethylsilane or methyltrichlorosilane; The difunctional siloxane is selected from methylvinyldimethoxysilane, phenylvinyldimethoxysilane, methylvinyldiethoxysilane, phenylvinyldiethoxysilane, diphenyldimethoxysilane or divinyldimethoxysilane, diphenyldiethoxysilane; The vinyl end-capping agent is selected from tetramethyldivinyldisiloxane and hexavinyldisiloxane.

2. The method for preparing the low-volatile adsorption thermosetting silicone resin for LED according to claim 1, characterized in that: Here are the steps: (1) Weighing vinyl silicone resin and hydrogen-containing crosslinking agent by weight; (2) Mix well at 100°C and cool to room temperature for later use; (3) adding a thickener and an inhibitor to the raw materials mixed uniformly in (2) and mixing them uniformly again; (4) adding the catalyst and thixotropic agent to the raw materials mixed uniformly in (3) and mixing uniformly; (5) The organic silicone resin mixed evenly in (4) is filtered and degassed to obtain the low-volatile adsorption thermosetting organic silicone resin for LED.

3. The use of the low-volatile adsorption thermosetting silicone resin for LED according to claim 1, characterized in that: The low-volatile adsorption thermosetting silicone resin for LED is used to bond the light-emitting chip and the silver-plated layer of the bracket in the white light LED field: the chip is bonded to the fixed position of the bracket using silicone resin through a crystal bonding machine, and then placed in a 160°C oven for 3 hours to complete curing, and then subsequent wire bonding and packaging processes are carried out.

Images