Semiconductor subassemblies with interconnects and methods for manufacturing the same

• US 8,188,601 B2
• Filed: 06/06/2007
• Issued: 05/29/2012
• Est. Priority Date: 06/06/2007
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Ward, Terence G., Yankoski, Edward P.
• Primary Examiner(s): Weiss, Howard
• Assistant Examiner(s): Rao, Steven
• Application Number:
  US11/758,859
• Publication Number:
  US 20080303056A1
• Time in Patent Office: 1,819 Days
• Field of Search: 257/723, 257/107, 257/706, 257/724, 361/760
• US Class Current: 257/753
• CPC Class Codes: H01L 2224/0603 Bonding areas having different sizes, e.g. different heights or widths
• CPC Class Codes: H01L 2224/37011 comprising apertures or cavities
• CPC Class Codes: H01L 2224/40091 Arched
• CPC Class Codes: H01L 2224/40225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/4103 Connectors having different sizes
• CPC Class Codes: H01L 2224/84801 Soldering or alloying
• CPC Class Codes: H01L 24/37 of an individual strap connector
• CPC Class Codes: H01L 24/40 of an individual strap connector
• CPC Class Codes: H01L 24/41 of a plurality of strap connectors
• CPC Class Codes: H01L 24/84 using a strap connector
• CPC Class Codes: H01L 25/072 the devices being arranged next to each other
• 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 2924/01004 Beryllium [Be]
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01029 Copper [Cu]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/1305 : Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/13055 : Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/13091 : Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/14 : Integrated circuits

Abstract

A semiconductor subassembly is provided for use in a switching module of an inverter circuit for a high power, alternating current motor application. The semiconductor subassembly includes a wafer having first and second opposed metallized faces; a semiconductor switching device electrically coupled to the first metallized face of the wafer and having at least one electrode region; and an interconnect bonded to the semiconductor switching device. The interconnect includes a first metal layer bonded to the at least one electrode region of the semiconductor switching device, a ceramic layer bonded to the first metal layer, the ceramic layer defining a via for accessing the first metal layer, a second metal layer bonded to the ceramic layer, and a conducting substance disposed in the via of the ceramic layer to electrically couple the first metal layer to the second metal layer.

Claims

1. A semiconductor subassembly for use in a switching module of an inverter circuit for a high power, alternating current motor application, the semiconductor subassembly comprising:

a wafer having first and second opposed metallized faces;

a semiconductor switching device electrically coupled to the first metallized face of the wafer and having at least one electrode region; and

an interconnect bonded to the semiconductor switching device, and including

a first metal layer bonded to the at least one electrode region of the semiconductor switching device,

a ceramic layer bonded to the first metal layer, the ceramic layer defining a via for accessing the first metal layer,

a second metal layer bonded to the ceramic layer, and

a conducting substance disposed in the via of the ceramic layer to electrically couple the first metal layer to the second metal layer, such that the second metal layer forms a contact pad for the at least one electrode region of the semiconductor switching device, wherein the conducting substance is substantially spherical.

2. The semiconductor subassembly of claim 1, wherein the at least one electrode region is a gate electrode region.

3. The semiconductor subassembly of claim 1, wherein the second metal layer completely covers the conducting substance and the via.

4. The semiconductor subassembly of claim 1, wherein the second metal layer includes a portion that covers the spherical conducting substance and the via, the portion being depressed to contact the spherical conducting substance.

5. The semiconductor subassembly of claim 1, wherein the ceramic layer has a first surface that defines a first area and the second metal layer has a first surface that defines a second area, the first area being approximately equal to the second area.

6. The semiconductor subassembly of claim 1, wherein the semiconductor switching device is an IGBT.

7. The semiconductor subassembly of claim 1, wherein the conducting substance is silver.

8. The semiconductor subassembly of claim 1, wherein the conducting substance is thick film.

9. The semiconductor subassembly of claim 1, further comprising a wire to electrically connect the conducting substance with the second metal layer.

14. The semiconductor subassembly of claim 1, wherein the conducting substance comprises a first material and the second layer comprises a second material, different from the first material.

16. The semiconductor subassembly of claim 1, wherein the first metal layer has a first coefficient of expansion and the second metal layer has a second coefficient of expansion, the first coefficient of expansion being approximately equal to the second coefficient of expansion.

17. The semiconductor subassembly of claim 1, wherein the first metal layer, the ceramic layer, and the second metal layer collectively have a first coefficient of expansion and the semiconductor switching device has a second coefficient of expansion, the first coefficient of expansion being approximately equal to the second coefficient of expansion.

10. A semiconductor module for use in an inverter circuit for a high power, alternating current motor application, the semiconductor module comprising:

a plurality of interconnected semiconductor subassemblies, each semiconductor subassembly comprising;

a wafer having first and second opposed metallized faces;

a semiconductor switching device electrically coupled to the first metallized face, wherein the semiconductor switching device includes a gate electrode region and a emitter electrode region; and

an interconnect bonded to the semiconductor switching device, and including

a first metal layer conductively bonded to the gate electrode region of the switching device,

a ceramic layer bonded to the first metal layer and defining a via for accessing the first metal layer,

a second metal layer bonded to the ceramic layer, and

a conducting substance disposed in the via of the ceramic layer to electrically couple the first metal layer to the second metal layer such that the second metal layer forms a contact pad for the gate electrode region of the semiconductor switching device, wherein the conducting substance is substantially spherical.

11. The semiconductor module of claim 10, wherein the second metal layer completely covers the conducting substance.

12. The semiconductor module of claim 10, wherein the second metal layer includes a portion that covers the spherical conducting substance and the via, the portion being depressed to contact the spherical conducting substance.

13. The semiconductor module of claim 10, wherein the ceramic layer has a first surface that defines a first area and the second metal layer has a first surface that defines a second area, the first area being approximately equal to the second area.

15. The semiconductor module of claim 10, wherein the conducting substance comprises a first material and the second layer comprises a second material, different from the first material.