Method of making a semiconductor chip assembly with a ceramic/metal substrate

• US 8,304,292 B1
• Filed: 08/03/2010
• Issued: 11/06/2012
• Est. Priority Date: 08/06/2009
• Status: Expired due to Fees

• Current Assignee: Bridge Semiconductor Corporation
• Original Assignee: Bridge Semiconductor Corporation
• Inventors: Lin, Charles W. C., Wang, Chia-Chung
• Primary Examiner(s): WILCZEWSKI, MARY A
• Application Number:
  US12/849,018
• Time in Patent Office: 826 Days
• Field of Search: 438/26, 438/121, 438/122, 438/124, 438/116, 257/E21.499
• US Class Current: 438/122
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/29144 Gold [Au] as principal constituent
• 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 2224/45144 Gold (Au) as principal constituent
• 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 2224/83 using a layer connector
• CPC Class Codes: H01L 2224/85 using a wire connector
• CPC Class Codes: H01L 23/142 Metallic substrates having insulating layers
• CPC Class Codes: H01L 23/3121 a substrate forming part of the encapsulation
• CPC Class Codes: H01L 23/36 Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks H01L23/28, H01L23/40, H01L23/42, H01L23/44, H01L23/46 take precedence; heating H01L23/345
• CPC Class Codes: H01L 23/498 Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers shape of the substrate H01L23/13
• CPC Class Codes: H01L 24/32 of an individual layer connector
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 24/48 of an individual wire 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 24/83 using a layer connector
• CPC Class Codes: H01L 24/85 using a wire connector wire bonding in general B23K20/004
• 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 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01028 : Nickel [Ni]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H01L 2924/351 : Thermal stress

Abstract

A method of making a semiconductor chip assembly includes providing a metal plate, providing a ceramic block in the metal plate, providing an insulative material in the metal plate, wherein the metal plate includes a base and a terminal, then providing a conductive layer on the base and the ceramic block, providing a conductive trace that includes a pad, the terminal and a selected portion of the conductive layer, then mounting a semiconductor device on the ceramic block, wherein a heat spreader includes the base and the ceramic block, electrically connecting the semiconductor device to the conductive trace and thermally connecting the semiconductor device to the heat spreader.

Claims

1. A method of making a semiconductor chip assembly, comprising:

providing a metal plate, wherein the metal plate includes a top surface that faces in an upward direction and a bottom surface that faces in a downward direction opposite the upward direction;

forming a cavity in the metal plate, wherein the cavity extends to the top surface of the metal plate, is spaced from the bottom surface of the metal plate and faces in the upward direction;

providing a ceramic block in the cavity;

forming a slot in the metal plate, wherein the slot extends to the bottom surface of the metal plate;

providing an insulative material in the slot;

wherein the metal plate includes a base and a terminal, the slot provides edges of the base and the terminal that face towards one another, the cavity extends into the base, the ceramic block contacts and is embedded in the base in the cavity and the insulative material contacts and is sandwiched between the base and the terminal in the slot;

then

depositing a conductive layer on the base, the terminal and the ceramic block;

then

providing a conductive trace that includes a pad and the terminal, wherein the conductive trace includes a selected portion of the conductive layer;

removing selected portions of the metal plate, thereby providing additional edges of the base and the terminal;

then

mounting a semiconductor device on the ceramic block, wherein a heat spreader includes the base and the ceramic block and the semiconductor device overlaps the ceramic block;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the ceramic block, thereby thermally connecting the semiconductor device to the base.

2. The method of claim 1, wherein providing the ceramic block includes:

forming an etch mask on the metal plate that selectively exposes the metal plate and defines the cavity;

etching the metal plate in a pattern defined by the etch mask, thereby forming the cavity in the metal plate;

then

removing the etch mask; and

then

providing the ceramic block in the cavity.

3. The method of claim 1, wherein providing the ceramic block includes depositing a slurry into the cavity and then sintering the slurry.

4. The method of claim 1, wherein the ceramic block contacts the insulative material and the terminal.

5. The method of claim 1, wherein the ceramic block is spaced from the insulative material and the terminal.

6. The method of claim 1, wherein providing the insulative material includes depositing an epoxy paste into the slot and then curing the epoxy paste.

7. The method of claim 1, including providing the ceramic block and then providing the insulative material.

8. The method of claim 1, including providing the insulative material and then providing the ceramic block.

9. The method of claim 1, wherein providing the conductive trace includes:

grinding the metal plate and the ceramic block such that the metal plate and the ceramic block are laterally aligned with one another at a top lateral surface that faces in the upward direction;

then

depositing the conductive layer on the top lateral surface; and

then

removing selected portions of the conductive layer.

10. The method of claim 1, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the ceramic block, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the ceramic block.

11. A method of making a semiconductor chip assembly, comprising:

providing a metal plate, wherein the metal plate includes a top surface that faces in an upward direction and a bottom surface that faces in a downward direction opposite the upward direction;

forming a cavity in the metal plate, wherein the cavity extends to the top surface of the metal plate, is spaced from the bottom surface of the metal plate and faces in the upward direction;

providing a ceramic block in the cavity;

forming a slot in the metal plate, wherein the slot extends to the bottom surface of the metal plate;

providing an insulative material in the slot;

wherein the metal plate includes a base and a terminal, the slot provides edges of the base and the terminal that face towards one another, the cavity extends into the base, the ceramic block contacts and is embedded in the base in the cavity and the insulative material contacts and is sandwiched between the base and the terminal in the slot;

then

depositing a conductive layer on the base, the terminal and the ceramic block;

then

providing a conductive trace that includes a pad and the terminal, wherein the conductive trace includes a selected portion of the conductive layer;

providing a cap on the ceramic block, wherein the cap includes a selected portion of the conductive layer;

removing selected portions of the metal plate, thereby providing additional edges of the base and the terminal;

then

mounting a semiconductor device on the cap, wherein a heat spreader includes the base, the ceramic block and the cap and the semiconductor device overlaps the ceramic block and the cap;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the cap, thereby thermally connecting the semiconductor device to the base.

12. The method of claim 11, wherein providing the ceramic block includes:

forming an etch mask on the metal plate that selectively exposes the metal plate and defines the cavity;

etching the metal plate in a pattern defined by the etch mask, thereby forming the cavity in the metal plate;

then

removing the etch mask;

then

depositing a slurry into the cavity; and

then

sintering the slurry, thereby providing the ceramic block in the cavity and embedding the ceramic block in the metal plate.

13. The method of claim 11, wherein providing the insulative material includes depositing an epoxy paste into the slot and then curing the epoxy paste.

14. The method of claim 11, wherein providing the conductive trace includes:

grinding the metal plate and the ceramic block such that the metal plate and the ceramic block are laterally aligned with one another at a top lateral surface that faces in the upward direction;

then

depositing the conductive layer on the top lateral surface; and

then

removing selected portions of the conductive layer using an etch mask that defines the pad and the cap.

15. The method of claim 11, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the cap, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the cap.

16. A method of making a semiconductor chip assembly, comprising:

providing a metal plate, wherein the metal plate includes a top surface that faces in an upward direction and a bottom surface that faces in a downward direction opposite the upward direction;

forming a first cavity in the metal plate, wherein the first cavity extends to the top surface of the metal plate, is spaced from the bottom surface of the metal plate and faces in the upward direction;

forming a second cavity in the metal plate, wherein the second cavity extends to the top surface of the metal plate, is spaced from the bottom surface of the metal plate and faces in the upward direction;

providing a first ceramic block in the first cavity;

providing a second ceramic block in the second cavity;

forming a slot in the metal plate, wherein the slot extends to the bottom surface of the metal plate;

providing an insulative material in the slot;

wherein the metal plate includes a base and a terminal, the slot provides edges of the base and the terminal that face towards one another, the first cavity extends into the base alone and is spaced from the slot, the second cavity extends into the base and the terminal and is adjacent to and overlaps the slot, the first ceramic block contacts and is embedded in the base alone in the first cavity, the second ceramic block contacts and is embedded in the base and the terminal in the second cavity and contacts the insulative material, and the insulative material contacts and is sandwiched between the base and the terminal in the slot;

then

depositing a conductive layer on the base, the terminal and the ceramic blocks;

then

providing a conductive trace that includes a pad and the terminal, wherein the conductive trace includes a selected portion of the conductive layer and contacts and overlaps the second ceramic block over the base, the terminal and the insulative material;

providing a cap that contacts and overlaps the first ceramic block, wherein the cap includes a selected portion of the conductive layer;

removing selected portions of the metal plate, thereby providing additional edges of the base and the terminal;

then

mounting a semiconductor device on the cap, wherein a heat spreader includes the base, the ceramic block and the cap and the semiconductor device overlaps the first ceramic block and the cap;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the cap, thereby thermally connecting the semiconductor device to the base.

17. The method of claim 16, wherein providing the ceramic blocks includes:

forming an etch mask on the metal plate that selectively exposes the metal plate and defines the cavities;

etching the metal plate in a pattern defined by the etch mask, thereby forming the cavities in the metal plate;

then

removing the etch mask;

then

depositing a slurry into the cavities; and

then

sintering the slurry, thereby providing the ceramic blocks in the cavities and embedding the ceramic blocks in the metal plate.

18. The method of claim 16, wherein providing the insulative material includes depositing an epoxy paste into the slot and then curing the epoxy paste.

19. The method of claim 16, wherein providing the conductive trace includes:

grinding the metal plate and the ceramic blocks such that the metal plate and the ceramic blocks are laterally aligned with one another at a top lateral surface that faces in the upward direction;

then

depositing the conductive layer on the top lateral surface; and

then

removing selected portions of the conductive layer using an etch mask that defines the pad and the cap.

20. The method of claim 16, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the cap, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the cap.