Heat spreaders for use with semiconductor devices

• US 10,410,950 B1
• Filed: 05/11/2018
• Issued: 09/10/2019
• Est. Priority Date: 05/11/2018
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Pax, George E.
• Primary Examiner(s): Le, Thao P
• Application Number:
  US15/977,760
• Time in Patent Office: 487 Days
• CPC Class Codes: H01L 2023/4068 Heatconductors between device and heatsink, e.g. compliant heat-spreaders, heat-conducting bands
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/73253 Bump and layer connectors
• CPC Class Codes: H01L 2224/92225 the second connecting process involving a layer connector
• CPC Class Codes: H01L 2225/06517 Bump or bump-like direct electrical connections from device to substrate
• CPC Class Codes: H01L 2225/06537 Electromagnetic shielding
• CPC Class Codes: H01L 2225/06572 Auxiliary carrier between devices, the carrier having an electrical connection structure
• CPC Class Codes: H01L 2225/06589 Thermal management, e.g. cooling
• 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 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 23/373 Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon
• CPC Class Codes: H01L 23/3736 Metallic materials H01L23/3732, H01L23/3733, H01L23/3735, H01L23/3737, H01L23/3738 take precedence
• CPC Class Codes: H01L 23/3737 Organic materials with or without a thermoconductive filler
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 24/32 of an individual layer connector
• CPC Class Codes: H01L 24/73 Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/92 Specific sequence of method steps
• CPC Class Codes: H01L 25/0652 the devices being arranged next and on each other, i.e. mixed assemblies
• CPC Class Codes: H01L 25/0657 Stacked arrangements of devices
• CPC Class Codes: H01L 25/50 : Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 2924/1431 : Logic devices
• CPC Class Codes: H01L 2924/1434 : Memory
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding

Abstract

Memory devices having heat spreaders are disclosed herein. In one embodiment, a memory device includes first memories coupled to a front side of a substrate, second memories coupled to a back side of the substrate, and a flexible heat spreader. The flexible heat spreader can include graphite and is coupled to back side surfaces of the first and second memories to dissipate heat generated by the first and second memories.

Claims

1. A heat spreader for use with a dual in-line memory module (DIMM), the heat spreader comprising:

a graphite member; and

a plastic covering enveloping the graphite member,

wherein the heat spreader is configured to be coupled to at least one of

a plurality of first memories electrically coupled to and arranged in one or more rows at a front side of a substrate of the DIMM, and

a plurality of second memories electrically coupled to and arranged in one or more rows at a back side of the substrate of the DIMM, and

wherein the graphite member includes

a first opening configured to be generally positioned over a first circuit component attached to the front side of the substrate of the DIMM, wherein the first opening is configured to inhibit a thermal path through the graphite member between the first circuit component and the first memories, and

a second opening configured to be generally positioned over a second circuit component attached to the front side of the substrate of the DIMM, wherein the second opening is configured to inhibit a thermal path through the graphite member between the second circuit component and the first memories.

2. The heat spreader of claim 1, wherein the first circuit component is a power management integrated circuit (PMIC).

3. The heat spreader of claim 1, wherein the second circuit component is a registering clock driver (RCD).

4. The heat spreader of claim 1, wherein:

the first circuit component is a PMIC,

the second circuit component is a RCD,

the first opening has a first cross-sectional dimension, and

the second opening has a second cross-sectional dimension, less than the first cross-sectional dimension.

5. The heat spreader of claim 1 wherein the plastic covering includes a thermoplastic material.

6. The heat spreader of claim 5 wherein the thermoplastic material is polyethylene terephthalate.

7. The heat spreader of claim 1, wherein the first circuit component is a voltage regulator.

8. The heat spreader of claim 1 wherein the first opening has a generally rectangular shape having a length of about 15 mm and a width of about 10 mm.

9. The heat spreader of claim 1 wherein the heat spreader is flexible, and wherein the heat spreader is configured to be attached to both the first and second memories such that it curves around an edge of the substrate.

10. The heat spreader of claim 9 wherein the heat spreader has a first length along a first edge of between about 120-130 mm, and a second length along a second edge of between about 45-55 mm, wherein the first edge is generally perpendicular to the second edge.

11. The heat spreader of claim 1 wherein

the graphite member is of a first heat spreader portion,

the first heat spreader portion is configured to be attached to substantially an entire back side of each of the first memories,

the heat spreader further comprises a graphite member of a second heat spreader portion, and

the second heat spreader portion is configured to be attached to substantially an entire back side of each of the second memories.

12. The heat spreader of claim 11 wherein the first and second heat spreader portions each have a rectangular shape with a length of between about 120-130 mm and a width of between about 20-30 mm.