Method to improve the reverse leakage characteristics in metal semiconductor contacts

• US 3,924,320 A
• Filed: 10/18/1974
• Issued: 12/09/1975
• Est. Priority Date: 04/14/1972
• Status: Expired due to Term

• Current Assignee: Akella V.S. Satya, Carl Altman, Sydney G. Chapman
• Original Assignee: Akella V.S. Satya, Carl Altman, Sydney G. Chapman
• Inventors: Altman, Carl, Chapman, Sydney G., Satya, Akella V. S.
• Primary Examiner(s): Tupman, W.
• Application Number:
  US05/516,236
• Time in Patent Office: 417 Days
• Field of Search: 29/576B,580,590,578 357/91,15
• US Class Current: 438/570
• CPC Class Codes: H01L 21/00 Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
• CPC Class Codes: H01L 21/2633 for etching, e.g. sputteretching
• CPC Class Codes: H01L 21/28537 Deposition of Schottky electrodes
• CPC Class Codes: H01L 29/47 Schottky barrier electrodes H01L29/435 takes precedence
• CPC Class Codes: H01L 29/872 Schottky diodes
• CPC Class Codes: Y10S 438/906 Cleaning of wafer as interim step

Abstract

A method for improving the reverse leakage characteristics in metal semiconductor contact devices is disclosed. The process embodies ionic plasma bombardment as a step in producing improved reverse bias current voltage characteristics between metal semiconductor contacts.

Claims

1. In a method for producing a metal P-type semiconductor contact diode wherein said metal has a work function higher than the electron affinity of the P-type substrate, said method including the following steps:

a. providing a P-type semiconductor substrate having an epitaxial layer thereon and covered by a suitable insulating or oxide film;

b. opening a contact hole through said layer;

c. chemically pre-cleaning the contact area on said substrate;

d. sputter cleaning the contact area on said substrate by subjecting said area to low energy ionic bombardment;

e. depositing metal in said contact hole and in contact with said contact area of said semiconductor substrate, whereby the metal P-type semiconductor diode has an improved reverse current characteristic.