Browse Prior Art Database

Cuprous Oxide (Cu2O) As an Effective Diffusion Barrier for Copper

IP.com Disclosure Number: IPCOM000102159D
Original Publication Date: 1990-Oct-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 1 page(s) / 31K

Publishing Venue

IBM

Related People

Aboelfotoh, MO: AUTHOR

Abstract

In this disclosure, a process is described which utilizes cuprous oxide (Cu2O) as an effective diffusion barrier for copper.

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

Cuprous Oxide (Cu2O) As an Effective Diffusion Barrier for Copper

       In this disclosure, a process is described which utilizes
cuprous oxide (Cu2O) as an effective diffusion barrier for copper.

      In the fabrication of silicon devices which use copper (Cu) as
interconnections metallization, W layer 14, as shown in the figure,
is first deposited over the exposed surface of the n+ diffused region
formed in the silicon substrate 10 through the window 22 formed in
the silicon oxide layer 12. A cuprous oxide (Cu2O) layer 16 is then
deposited to a thickness of 300 to 500 angstroms over the W layer 14
using a technique such as reactive sputtering in an oxygen
atmosphere.  This is followed by the deposition of a copper layer 18
to a thickness of 5000 to 8000 angstroms over the cuprous oxide layer
16 using a technique such as sputtering and a second layer 20 of
cuprous oxide to a thickness of 300 to 500 angstroms over the copper
layer 18.

      The advantage of the structure shown in the figure over prior
art is that a single metal, namely copper, and its oxide Cu2O are
used to form the conducting lines and the diffusion barrier in a
single process step.