Selectively cross-linked thermal interface materials

• US 10,050,010 B1
• Filed: 03/22/2017
• Issued: 08/14/2018
• Est. Priority Date: 03/22/2017
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Campbell, Eric J., Czaplewski, Sarah K., Labreck, Elin, Porto, Jennifer I.
• Primary Examiner(s): Trinh, Michael
• Application Number:
  US15/465,872
• Time in Patent Office: 510 Days
• CPC Class Codes: C09K 5/10 Liquid materials
• CPC Class Codes: H01L 2224/271 Manufacture and pre-treatment of the layer connector preform
• CPC Class Codes: H01L 2224/2731 in liquid form
• CPC Class Codes: H01L 2224/2755 Selective modification
• CPC Class Codes: H01L 2224/2783 Reworking, e.g. shaping reflowing H01L2224/27849
• CPC Class Codes: H01L 2224/2919 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/29191 The principal constituent being an elastomer, e.g. silicones, isoprene, neoprene
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/83101 as prepeg comprising a layer connector, e.g. provided in an insulating plate member
• CPC Class Codes: H01L 2224/83191 wherein the layer connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83192 wherein the layer connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83193 wherein the layer connectors are disposed on both the semiconductor or solid-state body and another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83201 Compression bonding
• CPC Class Codes: H01L 2224/83874 Ultraviolet [UV] curing
• CPC Class Codes: H01L 2224/83986 Specific sequence of steps, e.g. repetition of manufacturing steps, time sequence
• CPC Class Codes: H01L 23/367 Cooling facilitated by shape of device H01L23/38, H01L23/40, H01L23/42, H01L23/44, H01L23/46 take precedence
• CPC Class Codes: H01L 23/3675 characterised by the shape of the housing
• CPC Class Codes: H01L 23/3737 Organic materials with or without a thermoconductive filler
• CPC Class Codes: H01L 23/42 Fillings or auxiliary members in containers or encapsulations selected or arranged to facilitate heating or cooling
• CPC Class Codes: H01L 24/27 : Manufacturing methods
• CPC Class Codes: H01L 24/29 : of an individual layer connector
• CPC Class Codes: H01L 24/32 : of an individual layer connector
• CPC Class Codes: H01L 24/83 : using a layer connector
• CPC Class Codes: H01L 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/0625 : Polyvinyl alchohol
• CPC Class Codes: H01L 2924/0635 : Acrylic polymer
• CPC Class Codes: H01L 2924/0665 : Epoxy resin
• CPC Class Codes: H01L 2924/0715 : Polysiloxane
• CPC Class Codes: H01L 2924/1434 : Memory
• CPC Class Codes: H01L 2924/20211 : UV-C 100=<W<280 nm
• CPC Class Codes: H01L 2924/20212 : UV-B 280=<W<315 nm
• CPC Class Codes: H01L 2924/20213 : UV-A 315=<W<400 nm

Abstract

A process of forming a thermal interface material structure includes selectively masking a putty pad that includes ultraviolet (UV) curable cross-linkers to form a masked putty pad. The masked putty pad has a first area that is exposed and a second area that is masked. The process also includes exposing the masked putty pad to UV light to form a selectively cross-linked putty pad. The process includes disposing the selectively cross-linked putty pad between an electrical component and a heat spreader to form an assembly. The process further includes compressing the assembly to form a thermal interface material structure that includes a selectively cross-linked thermal interface material.

Claims

1. A thermal interface material structure comprising a selectively cross-linked thermal interface material, the selectively cross-linked thermal interface material including a first area having ultraviolet (UV) curable cross-linkers in a cross-linked state and a second area having the UV curable cross-linkers in a non-crosslinked state, wherein the selectively cross-linked thermal interface material corresponds to a single thermal interface material layer that defines an interface between a die and a heat spreader, and wherein the first area corresponds to outer edges of the interface.

2. The thermal interface material structure of claim 1, wherein the selectively cross-linked thermal interface material is formed from a selectively cross-linked putty pad.

3. The thermal interface material structure of claim 1, wherein the selectively cross-linked thermal interface material is formed from a grease that includes the UV curable cross-linkers.