Browse Prior Art Database

A Process for Submicron Contact Windows to Titanium Silicide

IP.com Disclosure Number: IPCOM000060105D
Original Publication Date: 1986-Feb-01
Included in the Prior Art Database: 2005-Mar-08
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Barber, J: AUTHOR [+2]

Abstract

The process disclosed can be used for etching contact windows in phosphosilicate glass (PSG)/Si02 film without damaging the thin TiSi2 layer underneath.

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

Page 1 of 1

A Process for Submicron Contact Windows to Titanium Silicide

The process disclosed can be used for etching contact windows in phosphosilicate glass (PSG)/Si02 film without damaging the thin TiSi2 layer underneath.

Step 1: Following the source/drain oxidation, a thin layer (1000 Angstroms) of Si3N4 is deposited on the thermal oxide.

Step 2: The usual thick layer (7000 Angstroms) of phosphosilicate glass is deposited using LPCVD techniq

Step 3: The contact level is defined using conventional photolithographic processes.

Step 4: The contact windows are reactive ion etched (RIE) as follows: A. CClF3H2 is used to etch the PSG to the Si3N4 layer. A substantial overetch (40%) is used to ensure that all windows are open to the Si3N4 . The Si3N4 serves as a buffer layer to absorb the etch depth non- uniformities produced by the RIE of the thick PSG layer. B. CF4-H2 is used to etch the Si3N4 and Si02 to the TiSi2 . Because of the thin layer to be etched, the etch depth non-uniformity is minimal and the overetch needed is less than 10%.

With this process, the TiSi2 layer is undamaged by the contact window RIE process.

Disclosed anonymously.

1