Semiconductor device

• US 6,768,188 B2
• Filed: 06/19/2003
• Issued: 07/27/2004
• Est. Priority Date: 09/19/2002
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Moriguchi, Koji
• Primary Examiner(s): Cuneo, Kamand
• Assistant Examiner(s): Tran, Thanh Y.
• Application Number:
  US10/464,752
• Publication Number:
  US 20040056362A1
• Time in Patent Office: 404 Days
• Field of Search: 361/764, 361/772, 361/773, 361/774, 361/791, 361/813, 257/690, 257/735, 257/773, 257/666, 257/669, 257/693, 257/676
• US Class Current: 257/676
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/371 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/4007 of bonding interfaces, e.g. interlocking features
• CPC Class Codes: H01L 2224/40245 the item being metallic
• CPC Class Codes: H01L 2224/83801 Soldering or alloying
• CPC Class Codes: H01L 2224/84345 Shape, e.g. interlocking features
• CPC Class Codes: H01L 2224/84801 Soldering or alloying
• CPC Class Codes: H01L 23/49524 the additional leads being a tape carrier or flat leads
• CPC Class Codes: H01L 23/49562 for devices being provided for in H01L29/00
• 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 24/84 using a strap 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 2924/01004 Beryllium [Be]
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01015 Phosphorus [P]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/12036 : PN diode
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/30105 : Capacitance
• CPC Class Codes: H01L 2924/351 : Thermal stress

Abstract

There is provided a semiconductor device in a package structure that can improve reliability. The semiconductor device comprises a semiconductor chip having an upper electrode and a lower electrode formed thereon; a package base bonded to the lower electrode on the semiconductor chip; and a metallic strap having first and second ends bonded through solders to the upper electrode on the semiconductor chip and a package lead. The first end of the metallic strap is bonded to the upper electrode in such a manner that a gap therebetween gradually becomes wider in a portion close to the semiconductor chip'"'"'s edge toward said second end of said metallic strap.

Claims

1. A semiconductor device, comprising:

a semiconductor chip having an upper electrode and a lower electrode formed thereon;

a package base bonded to said lower electrode on said semiconductor chip; and

a metallic strap having first and second ends, said first ends being bonded via a solder to said upper electrode on said semiconductor chip, said second end being bonded to a package lead, wherein said first end of said metallic strap is bonded to said upper electrode in such a manner that a gap therebetween gradually becomes wider in a portion close to said semiconductor chip'"'"'s edge toward said second end of said metallic strap, and

wherein said first end of said metallic strap has a conical shape with a vertical angle toward said semiconductor chip.

2. The semiconductor device as recited in claim 1, wherein said conical shape has a rounded apex.

3. The semiconductor device as recited in claim 1, wherein said pyramidal shape has a rounded apex.

4. The semiconductor device as recited in claim 1, wherein said vertical angle is determined within 9-170°

.

5. The semiconductor device as recited in claim 1, wherein said package base is tilted to a package lead plane in such a manner that one side of the package base toward said package lead is lowered than the other.

6. The semiconductor device as recited in claim 1, wherein said package base is tilted to said package lead plane in such a manner that one side of the package base toward a package lead is lowered than the other.

7. A semiconductor device, comprising:

a semiconductor chip having an upper electrode and a lower electrode formed thereon;

a package base bonded to said lower electrode on said semiconductor chip; and

a metallic strap having first and second ends, said first ends being bonded via a solder to said upper electrode on said semiconductor chip, said second end being bonded to a package lead, wherein said first end of said metallic strap is bonded to said upper electrode in such a manner that a gap therebetween gradually becomes wider in a portion close to said semiconductor chip'"'"'s edge toward said second end of said metallic strap, and

wherein said first end of said metallic strap has a pyramidal shape with a vertical angle toward said semiconductor chip.