Conformal diamond coating for thermal improvement of electronic packages

• US 5,907,189 A
• Filed: 05/29/1997
• Issued: 05/25/1999
• Est. Priority Date: 05/29/1997
• Status: Expired due to Term

• Current Assignee: Bell Semiconductor, LLC (Hilco Inc. (d/b/a Hilco Global))
• Original Assignee: LSI Logic Corporation (Broadcom, Inc.)
• Inventors: Mertol, Atila
• Primary Examiner(s): WILLIAMS, ALEXANDER O
• Application Number:
  US08/864,994
• Time in Patent Office: 726 Days
• Field of Search: 257/787, 257/712, 257/704, 257/717, 257/726, 257/723, 257/706, 257/713, 257/796, 257/975, 257/77, 257/719, 257/627, 257/701, 257/737, 257/738, 257/741, 257/788, 257/789
• US Class Current: 257/787
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• 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 23/3732 Diamonds
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• 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 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/0102 Calcium [Ca]
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/207 Diameter ranges

Abstract

One aspect of the invention relates to a method for providing a semiconductor package with a thermally conductive coating, the semiconductor package including a package substrate having a plurality of electrically conductive traces formed thereon, an upper surface and a lower surface, the lower surface having a plurality of contacts for providing electrical connection between the conductive traces formed on the package substrate and a plurality of conductive traces formed on a printed circuit board, and a semiconductor die mounted to the upper surface to the package substrate, the semiconductor die having a plurality of bond pads formed thereon which are electrically connected to the conductive traces formed on the package substrate. In one embodiment, the method includes the steps of depositing a coating on the upper surface of the package substrate and the coating includes a diamond film or diamond particles.

Claims

1. A semiconductor package, comprising:

a package substrate having a plurality of electrically conductive traces formed thereon, an upper surface and a lower surface, the lower surface having a plurality of contacts for providing electrical connection between the conductive traces formed on the package substrate and a plurality of conductive traces formed on a printed circuit board;

a semiconductor die with an upper surface and a lower surface, the lower surface of the semiconductor die mounted to the upper surface of the package substrate, the semiconductor die having a plurality of bond pads formed thereon which are electrically connected to the conductive traces formed on the package substrate;

a coating disposed on at least part of the upper surface of the package substrate and at least part of the upper surface of the semiconductor die, the coating comprising diamond.

2. A semiconductor package as in claim 1 wherein the coating is deposited on the package substrate by chemical vapor deposition.

3. A semiconductor package as in claim 1 wherein the coating comprises a preformed diamond structure.

4. A semiconductor package, comprising:

a package substrate having a plurality of electrically conductive traces formed thereon, an upper surface and a lower surface, the lower surface having a plurality of contacts for providing electrical connection between the conductive traces formed on the package substrate and a plurality of conductive traces formed on a printed circuit board;

a semiconductor die with an upper surface and a lower surface, the lower surface of the semiconductor die mounted to the upper surface of the package substrate, the semiconductor die having a plurality of bond pads formed thereon which are electrically connected to the conductive traces formed on the package substrate;

a coating disposed on at least part of the upper surface of the package substrate and at least part of the upper surface of the semiconductor die, the coating comprising diamond;

a heat sink for transferring heat away from the semiconductor die, the heat sink being attached to the diamond coating disposed on the upper surface of the package substrate.

5. A semiconductor package as in claim 4 wherein the coating is a chemical vapor deposition.

6. A semiconductor package as in claim 4 wherein the coating comprises a preformed diamond structure.

7. A semiconductor package as in claim 4 wherein the heat sink comprises a plurality of cooling fins.