Optimization of
Metal Adhesion for GaAs Backside Wafer Processing
Terry Daly, Jason
Fender, Bob Duffin, Mike Kottke
Compound
Semiconductor-1 Motorola, Inc.
2100 E. Elliot Rd. MD
EL609,
Phone: 480-413-5029,
email: rp5060@email.sps.mot.com
Keywords: metal, adhesion,
backside processing
Abstract
Through use of analytical
techniques and process monitors, we have studied metal adhesion to the wafer backside
following through-substrate via processing. It was discovered that metal
adhesion could be controlled by GaAs surface preparation with wet chemistry, RF
pre-metal deposition sputter etch, and target crystallinity due to sputter
power. Our results are based on Auger electron spectroscopy, optical
reflectometry, atomic force microscopy, x-ray pole figures, and a test we
developed to evaluate practical work of adhesion.