Browse Prior Art Database

Nickel Silicide Barriers to Improve Ohmic Contacts

IP.com Disclosure Number: IPCOM000082302D
Original Publication Date: 1974-Nov-01
Included in the Prior Art Database: 2005-Feb-28
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Dahmen, M: AUTHOR [+4]

Abstract

A thin continuous layer of nickel-silicide improves the properties of ohmic contacts between a strongly n-doped silicon substrate and the Al/Cu metallization, and prevents, in particular, the penetration of Al spikes into the silicon.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Nickel Silicide Barriers to Improve Ohmic Contacts

A thin continuous layer of nickel-silicide improves the properties of ohmic contacts between a strongly n-doped silicon substrate and the Al/Cu metallization, and prevents, in particular, the penetration of Al spikes into the silicon.

Ohmic contacts to the active areas in silicon substrates are generally made through contact holes in a layer of dielectric material, such as SiO(2), covering the substrate. After the contact holes have been etched, a nickel film of about 1000 angstroms thickness is vapor deposited on the substrate at a temperature below 50 degrees C.

Subsequently, all the nickel in the contact holes reacts with the silicon within 20 min at 450 degrees C in a nonoxidizing atmosphere, such as forming gas, to form nickel-silicide. The nickel covering the dielectric layer is etched away. This is followed by the conventional Al/Cu metallization process.

1