Nitride semiconductor wafer

• US 7,872,331 B2
• Filed: 02/16/2009
• Issued: 01/18/2011
• Est. Priority Date: 02/27/2008
• Status: Active Grant

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Mikami, Hidenori, Matsumoto, Naoki, Ishibashi, Keiji
• Primary Examiner(s): Soward; Ida M
• Application Number:
  US12/812,697
• Publication Number:
  US 20100270649A1
• Time in Patent Office: 701 Days
• Field of Search: 257/496, 257/613, 257/615, 257/618, 257/798, 257/E21.085, 257/E21.214, 257/E21.222, 257/E21.237, 257/E21.239
• US Class Current: 257/618
• CPC Class Codes: C30B 29/403 AIII-nitrides
• CPC Class Codes: C30B 33/00 After-treatment of single crystals or homogeneous polycrystalline material with defined structure C30B31/00 takes precedence
• CPC Class Codes: H01L 21/02021 Edge treatment, chamfering
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 24/32 of an individual layer 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 2924/00014 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 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: Y10S 438/928 Front and rear surface processing
• CPC Class Codes: Y10S 438/959 Mechanical polishing of wafer
• CPC Class Codes: Y10S 438/977 Thinning or removal of substrate

Abstract

A nitride semiconductor wafer is planar-processed by grinding a bottom surface of the wafer, etching the bottom surface by, e.g., KOH for removing a bottom process-induced degradation layer, chamfering by a rubber whetstone bonded with 100 wt %-60 wt % #3000-#600 diamond granules and 0 wt %-40 wt % oxide granules, grinding and polishing a top surface of the wafer, etching the top surface for eliminating a top process-induced degradation layer and maintaining a 0.5 μm-10 μm thick edge process-induced degradation layer.

Claims

1. A nitride semiconductor wafer having a chamfered edge, a 0.5 μ

m-10 μ

m thick edge process-induced degradation layer with a deformed lattice structure remaining on the chamfered edge and a mirror-flat top surface.

2. The nitride semiconductor wafer as claimed in claim 1, wherein edge roughness is Ra0.07 μ

m to Ra3 μ

m.

3. The nitride semiconductor wafer as claimed in claim 1, wherein edge oxygen concentration is 3 at % to 20 at %.

4. The nitride semiconductor wafer as claimed in claim 2, wherein edge oxygen concentration is 3 at % to 20 at %.

5. The nitride semiconductor wafer as claimed in claim 1, wherein edge metal concentration is 0.1 at % to 5 at %.

6. The nitride semiconductor wafer as claimed in claim 2, wherein edge metal concentration is 0.1 at % to 5 at %.

7. The nitride semiconductor wafer as claimed in claim 3, wherein edge metal concentration is 0.1 at % to 5 at %.

8. The nitride semiconductor wafer as claimed in claim 4, wherein edge metal concentration is 0.1 at % to 5 at %.

9. A nitride semiconductor wafer having a chamfered edge formed by a rubber-bonding whetstone, a 1 μ

m-3 μ

m thick edge process-induced degradation layer with a deformed lattice structure remaining on the chamfered edge, and a minor-flat top surface.