Electron Cyclotron Resonance (ECR) Semiconductor Etching Process Control by Ellipsometry

Period of Performance: 08/03/1993 - 08/03/1995


Phase 2 SBIR

Recipient Firm

J.a. Woollam CO.
Lincoln, NE 68508
Principal Investigator


The need for smaller semiconductor device structures for use in very high speed microelectronics requires a new generation of plasma etching technology. ECR promises to provide features as small as 0.2 microns in size, as well as a high degree of etching anisotropy, selectivity, etch rates, and low damage. For manufacturing process control involving ECR etching in production of electronics and opto-electronics on silicon and compound semiconductors, considerable further research and development is needed. Spectroscopic ellipsometry uses polarized light reflectance, and has sensitivity to surface and interface effects a fraction of an atomic monolayer thick. Thus surface damage, surface roughness, and surface compound/alloy stoichiometry can be determined. We recently developed the ability to convert ellipsometric psi and delta data in real time into desired materials properties such as thickness, alloy ratio, surface temperature during semiconductor crystal growth. The purpose of the proposed Phase II research is to implement control of ECR etching processing using spectroscopic ellipsometry. Control of ECR etching of Si, GaAs, InP, InGaAs, and HgCdTe semiconductor materials, as well as aluminum and its oxide, will be implemented. One final aspect of this contract is the follow-on Phase III commercialization. To better understand the real industrial environment and needs, we will carry out demonstration-type experiments at Texas Instruments Inc. facilities in Dallas towards the end of the Phase II work.