Process for producing a semiconductor device with a roughened semiconductor surface

• US 6,309,953 B1
• Filed: 03/02/2000
• Issued: 10/30/2001
• Est. Priority Date: 02/23/1995
• Status: Expired due to Term

• Current Assignee: OSRAM GmbH (Ams-Osram AG)
• Original Assignee: Siemens AG
• Inventors: Fischer, Helmut, Sedlmeier, Reinhard, Nirschl, Ernst, Lang, Gisela
• Primary Examiner(s): Chaudhuri, Olik
• Assistant Examiner(s): DOAN, THERESA T
• Application Number:
  US09/517,299
• Time in Patent Office: 607 Days
• Field of Search: 438/33, 438/606, 438/572, 438/464, 438/751, 257/13
• US Class Current: 438/606
• CPC Class Codes: H01L 29/0657 characterised by the shape of the body
• 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 2924/10156 at the periphery
• CPC Class Codes: H01L 2924/10157 at the active surface
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/40 Materials therefor

Abstract

A process for producing a semiconductor device includes the following sequential steps: producing a semiconductor body having an Al_xGa_1−xAs layer with an upper surface, where x≦0.40; applying a contact metallization made of a non-noble metallic material to the Al_xGa_1−xAs layer; precleaning a semiconductor surface to produce a hydrophilic semiconductor surface; roughening the upper surface of the Al_xGa_1−xAs layer by etching with an etching mixture of hydrogen peroxide ≧30% and hydrofluoric acid ≧40% (1000:6) for a period of from 1 to 2.5 minutes; and re-etching with a dilute mineral acid. According to another embodiment, 0≦x≦1 and the upper surface of the Al_xGa_1−xAs layer is roughened by etching with nitric acid 65% at temperatures of between 0° C. and 30° C.

Claims

1. A process for producing a semiconductor device, which comprises the following sequential steps:

a) producing a semiconductor body having an Al_xGa<sub>1−

x</sub>As layer with an upper surface, where 0≦

x ≦

1;

b) applying a contact metallization made of a non-noble metallic material to the Al_xGa<sub>1−

x</sub>As layer;

c) precleaning a semiconductor surface to produce a hydrophilic semiconductor surface; and

d) roughening the upper surface of the Al_xGa<sub>1−

x</sub>As layer by etching with nitric acid 65% at temperatures of between 0°

C. and 30°

C.

2. The process according to claim 1, which comprises forming the contact metallization of aluminum.

3. The process according to claim 1, which comprises forming the contact metallization of an aluminum-based alloy.

4. The process according to claim 1, which comprises additionally roughening at least sub-regions of lateral surfaces of the semiconductor body.