Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Diffusion Barrier in Polycrystalline Metal Film By Grain Boundary Oxidation

IP.com Disclosure Number: IPCOM000086372D
Original Publication Date: 1976-Aug-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 2 page(s) / 43K

Publishing Venue

IBM

Related People

Campbell, DR: AUTHOR [+3]

Abstract

Rapid diffusion along grain boundaries or dislocations in thin films will reduce the effectiveness of metal layers employed as diffusion barriers. This problem can be avoided by oxidizing the structural defects.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 55% of the total text.

Page 1 of 2

Diffusion Barrier in Polycrystalline Metal Film By Grain Boundary Oxidation

Rapid diffusion along grain boundaries or dislocations in thin films will reduce the effectiveness of metal layers employed as diffusion barriers. This problem can be avoided by oxidizing the structural defects.

Thin polycrystalline metal films are used in the semiconductor industry. A conducting stripe of Au or Au alloy is an example. Due to problems of poor adhesion or reactivity, Au films are often used in conjunction with other metals such as Cr, Ta and Mo, which have the dual purpose of improving adhesion to substrates and acting as a barrier to diffusion.

When polycrystalline layers are employed as diffusion barriers they have only limited effectiveness. Diffusion of the overlay material through the interior of grains may be quite slow, but it can be quite rapid along the grain boundaries even at room temperature. Such low-temperature diffusion processes are detrimental to device reliability and electrical resistivity. A technology for inhibiting diffusion along the grain boundaries of metal films is desirable.

Rapid diffusion along grain boundaries depends upon the existence of regions of structural disorder where atomic mobility is high. If the high mobility sites can be occupied or bound with immobile atoms, the diffusion rate will be diminished. One way of introducing immobilizing impurities into the boundaries is by heating the film in the presence of reactive gases such as O(2...