Substrate for optical semiconductor

• US 20060269698A1
• Filed: 09/21/2004
• Published: 11/30/2006
• Est. Priority Date: 09/22/2003
• Status: Abandoned Application

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Materials Company Limited (Toshiba Corporation)
• Original Assignee: Tohiba Materials Company Limited, Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Nakamura, Miho, Shirai, Takao
• Application Number:
  US10/547,697
• Publication Number:
  US 20060269698A1
• Time in Patent Office: Days
• US Class Current: 428/1.600
• CPC Class Codes: C09K 2323/06 Substrate layer characterised by chemical composition
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/641 characterized by the materials
• CPC Class Codes: H01S 5/0237 by soldering
• CPC Class Codes: H01S 5/02476 Heat spreaders, i.e. improving heat flow between laser chip and heat dissipating elements

Abstract

A substrate for optical semiconductors of the present invention comprises an insulating ceramic substrate, a metal layer provided on the insulating ceramic substrate, a solder layer provided on the metal layer and composed of Sn only or 50 wt % or more of Sn and the balance substantially of Au, and a protective layer provided on the solder layer and composed of Au or Ag having a thickness of 0.01 μm or more and 1 μm or less. The substrate for optical semiconductors as described above makes it possible to reduce stress placed on the optical semiconductor, to suppress development of crystal defects, and to prolong its life when joining the optical semiconductor easily developing crystal defects by slight stress or when in use thereafter.

Claims

1. A substrate for an optical semiconductor, comprising:

an insulating ceramic substrate;

a metal layer provided on said insulating ceramic substrate;

a solder layer provided on said metal layer and composed of Sn only or 50 wt % or more of Sn and the balance substantially of Au; and

a protective layer provided on the solder layer and composed of Au or Ag having a thickness of 0.01 μ

m or more and 1 μ

m or less.

2. A substrate for an optical semiconductor according to claim 1,

wherein said solder layer has a thickness of 2 μ

m or more and 5 μ

m or less.

3. A substrate for an optical semiconductor according to claim 1,

wherein said insulating ceramic substrate contains one kind selected from aluminum nitride, silicon nitride, silicon carbide, beryllium oxide and diamond as a main component.

4. A substrate for an optical semiconductor according to claim 3,

wherein said insulating ceramic substrate has thermal conductivity of 80 W/m·

K or more.