Silicone pad with excellent uniformity

Abstract

Provided is a silicone pad manufactured by curing a liquid silicone resin containing dimethyl siloxane and methylvinylsiloxane, characterized in that after curing, the silicone pad has an elongation (%) in the range of 400 to 500, a compression set (%) in the range of 0.5 to 0.6, a weight average molecular weight (g / mol) in the range of 40,000 to 60,000, and an average molecular weight (g / mol) in the range of 0.5 to 0.6. The silicone pad has a number average molecular weight (g / mol) of 1000 to 2000, whereby the silicone pad has a uniformity with a step difference of 70 [mu] m or less when pressurized at 90 kgf / cm2 at a length of 50 cm or more.

Description

Technical Field

[0001] The present invention relates to a silicone resin pad having excellent uniformity, and more particularly, to a silicone resin pad having excellent uniformity that can be pressed and mounted with excellent uniformity when an electronic component such as a semiconductor chip is pressed. Background Art

[0002] As semiconductor line widths continue to shrink, various packaging technologies are being developed. However, this packaging process requires technology to stack chips in multiple layers, which requires the use of rubber-based gaskets such as silicone.

[0003] However, as the area of ​​such silicone rubber pads increases, there is a problem of reduced uniformity across the entire area when pressurizing for mounting electronic components such as chips. Therefore, it is necessary to develop a new silicone rubber pad that can solve these problems. Summary of the Invention

[0004] Technical issues Therefore, one problem to be solved by the present invention is to provide a silicone pad having excellent uniformity and a method for manufacturing the same.

[0005] Technical Solution In order to solve the technical problem, the present invention provides a silicone resin pad, which is a silicone resin pad manufactured by curing a liquid silicone resin containing dimethylsiloxane and methylvinylsiloxane, characterized in that after curing, the silicone resin pad has an elongation in the range of 400% to 500%, a compression permanent deformation rate of 0.5% to 0.6%, a weight average molecular weight of 40,000 g / mol to 60,000 g / mol, a number average molecular weight of 1000 g / mol to 2000 g / mol, and a silicone resin pad with a length of more than 50 cm and a pressure of 90 kgf / cm 2 When pressurized, the uniformity of the step difference is within 70μm.

[0006] In one embodiment of the present invention, the silicone resin pad is a compression pad for semiconductor packaging.

[0007] In one embodiment of the present invention, the size of the silicone resin pad is greater than 50 cm×50 cm. The curing time of the silicone resin pad is 5 to 15 minutes, and the curing temperature is 100° C.

[0008] Technical Effects According to the silicon mat of the present invention, excellent uniformity can be obtained when pressurized based on the combination of elongation and compression set, and the uniformity can be constantly maintained particularly over a large area. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figures 1 to 4 This is the extrusion test result of the silicon pad.

[0010] Figures 5 to 7 The results of measuring the uniformity of the mats are obtained by increasing the length and width of the mats from 10 cm to 50 cm and 100 cm in Example 1 and Comparative Examples 1 and 3, respectively.

[0011] Best Mode for Carrying Out the Invention Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0012] Before describing the present invention in detail, the terms and words used in this specification should not be interpreted unconditionally and limitedly according to their conventional or dictionary meanings. The inventors of the present invention may appropriately define the concepts of various terms and use them in order to describe their invention in the best way.

[0013] Furthermore, it should be understood that these terms or words should be interpreted as meanings and concepts consistent with the technical ideas of the present invention.

[0014] That is, the terms used in this specification are only used to describe the preferred embodiments of the present invention, and are not intended to specifically limit the contents of the present invention.

[0015] It should be understood that these terms are terms defined in consideration of various possibilities of the present invention.

[0016] Furthermore, in this specification, a singular expression may include a plural expression unless the context clearly indicates otherwise.

[0017] In addition, it should be understood that even if a plural number is expressed, the singular number may also be included.

[0018] Throughout this specification, when it is stated that a certain component “includes” other components, unless otherwise clearly indicated to the contrary, it may mean that any other components may also be included rather than excluding any other components.

[0019] In one embodiment of the present invention, it was discovered that the combination of the compression set and elongation of the silicone rubber has a significant effect on the uniformity of the pad during crimping.

[0020] Hereinafter, the present invention will be described in more detail with reference to examples. DETAILED DESCRIPTION

[0021] Example In one embodiment of the present invention, liquid silicone rubber (LSR) is cured at a temperature of 100 degrees Celsius in a size of 100 cm×100 cm and a thickness of 3 mm.

[0022] In the present invention, 50 to 60 parts by weight of methylvinylsiloxane relative to 100 parts by weight of dimethylsiloxane is cured in a curing mold in the presence of a platinum catalyst (5 parts by weight) at a temperature of 150° C. for 5 minutes, thereby preparing a liquid silicone rubber.

[0023] As a comparative example, the silicone resin is LSR, which is a liquid silicone rubber resin obtained by copolymerization of dimethylsiloxane and methylvinylsiloxane, but has a different molecular weight.

[0024] To this end, 10 parts by weight of methylvinylsiloxane (Comparative Example 1) and 100 parts by weight of methylvinylsiloxane were used relative to 100 parts by weight of dimethylsiloxane, respectively, and a platinum catalyst (5 parts by weight) was used. The mixture was cured in a curing mold at 150°C for 5 minutes to prepare a liquid silicone rubber (Comparative Example 2).

[0025] Separately, the curing time was set to 20 minutes instead of 5 minutes, and 200 parts by weight of methylvinylsiloxane was cured with respect to 100 parts by weight of dimethylsiloxane (Comparative Example 3).

[0026] The molecular weights of Examples and Comparative Examples are as follows.

[0027]

Table 1

[0028] The molecular weight measurement is based on the GPC method, which calculates the molecular weight and distribution by setting the portion of the baseline close to 0 or the lowest point as the endpoint. Referring to the results, it can be seen that there is a significant difference in number average molecular weight between the Examples and Comparative Examples.

[0029] Experimental Example 1 In this experimental example, the elongation (% modulus) according to ASTM D412 die-C and the compression set according to ASTM D395 method-B were compared.

[0030]

Table 2

[0031] Figures 1 to 4 The compression test results of the silicon pads of Example and Comparative Examples 1 to 3 are shown respectively.

[0032] In one embodiment of the present invention, the pressure-reducing paper is subjected to a pressure of 90 kgf / cm 2 The fabricated silicon wafer is pressed as a metal plate with a force of 1.5 Å.

[0033] Reference Figures 1 to 4 , it can be seen that the combination of an elongation of 400 to 500 and a compression set of 0.5 to 0.6 shows excellent uniformity. The darker the color, the stronger the pressure.

[0034] Comparative Example 2, which has an elongation similar to that of the embodiment, has a compression set exceeding 0.7, indicating reduced uniformity. Conversely, Comparative Example 3, which has a similar compression set, has a significantly greater elongation than the silicon mat of the present invention, but in this case, uniformity is inferior to that of the present invention.

[0035] Therefore, the silicon pad of the present invention has an elongation in the range of 400% to 550% and a compression set in the range of 0.5% to 0.65%. If either of these two conditions exceeds this range, it is difficult to obtain the desired uniformity (step difference within 70 μm) as described above.

[0036] Experimental Example 2 The silicon mat according to the present invention having the above characteristics particularly exhibits excellent uniformity over a large area on the level of about 100 cm×100 cm.

[0037] Figures 5 to 7 The length and width of the embodiment and comparative example 1 and comparative example 3 were increased from 10 cm to 50 cm and 100 cm respectively, and the 2 The force measurements are a measure of the uniformity of the pad.

[0038] Reference Figures 5 to 7 , it can be seen that as the size of the pad increases, the uniformity deteriorates in the cases of Comparative Examples 1 and 3. However, in the case of the present invention, it can be seen that despite the increase in size, the uniformity remains constant. Therefore, the above results show that when the silicon pad according to one embodiment of the present invention has a minimum length and width (i.e., size) of at least 50 cm, it has a uniformity of a step difference within 70 μm. In addition, the curing time is less than 5 minutes to 20 minutes, and more preferably, the curing time is 5 minutes to 15 minutes or less.

[0039] Thus, the silicone resin pad according to the present invention has a weight average molecular weight (Mw) of 40,000-60,000 in terms of molecular weight, while having a number average molecular weight (Mn) of not more than 2000 (preferably 1500-2000).

[0040] The experimental results above demonstrate that this molecular weight combination can affect uniformity particularly when applying pressure to large silicon pads (minimum 50 cm or larger). Specifically, these results suggest that, under conditions of equal weight, the greater the presence of polymers with longer molecular chains (i.e., a wider distribution of polymers), the more favorable the uniformity achieved on large-area substrates during pressure application.

[0041] Industrial Applicability The present invention is considered to have industrial applicability as a silicone resin pad having excellent uniformity.

Claims

1. A silicone resin pad made by curing a liquid silicone resin containing dimethylsiloxane and methylvinylsiloxane, characterized in that: After curing, the silicone resin pad has an elongation of 400% to 500% and a compression set of 0.5% to 0.6%. The weight average molecular weight of the silicone resin pad is 40,000 g / mol to 60,000 g / mol, and the number average molecular weight is 1000 g / mol to 2000 g / mol. Thus, the silicone resin pad can withstand a load of 90 kgf / cm2 at a length of 50 cm or more. 2 When pressurized, the uniformity of the step difference is within 70μm.

2. The silicone resin pad according to claim 1, wherein The silicone resin pad is a compression pad for semiconductor packaging.

3. The silicone resin pad according to claim 2, characterized in that The size of the silicone resin pad is greater than 50 cm×50 cm.

4. The silicone resin pad according to claim 1, characterized in that The curing time of the silicone resin pad is 5 to 15 minutes, and the curing temperature is 100°C.

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