Electron cyclotron resonance etching characteristics of GaN in plasmas with and without hydrogen

Book · Thu Oct 31 23:00:00 EST 1996

OSTI ID:395031

Zhang, L; Ramer, J; Brown, J; Zheng, K; Lester, L F; Hersee, S D ^[1]

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1. Univ. of New Mexico, Albuquerque, NM (United States). Center for High Technology Materials

Electron cyclotron resonance (ECR) plasma etching characteristics of gallium nitride (GaN) are investigated using low pressure (4--10 mTorr) SiCl{sub 4}/Ar and Cl{sub 2}/H{sub 2}/Ar ECR discharges. The purpose of this effort is to develop a dry etching process for making laser mirrors on GaN and to examine dry etching processes of GaN that do not require hydrogen, which is known to cause carrier compensation in GaN. The etch rate is found to increase near-linearly with increasing DC bias, and a minimum DC bias of 100V is required to initiate etching in SiCl{sub 4}/Ar. The authors have also found that the material quality significantly affects the etch rate. The latter decreases with x-ray rocking curve half-width and increases with defect density. A reasonable etch rate of 660 {angstrom}/min and good surface morphologies obtained in SiCl{sub 4}/Ar ECR etching make this process suitable for gate recess of an FET. An etch rate of 5,270 {angstrom}/min has been achieved in Cl{sub 2}/H{sub 2}/Ar plasmas. This is the highest reported etch rate of GaN so far. The smooth and vertical etch sidewalls (etch to mask selectivity of 16 is obtained) make this process promising for dry-etched laser mirrors on GaN.

• OSTI ID: 395031
• Report Number(s): CONF-951155--; ISBN 1-55899-298-7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
ARGON
CHEMICAL VAPOR DEPOSITION
ELECTRONIC EQUIPMENT
ETCHING
EXPERIMENTAL DATA
GALLIUM NITRIDES
HYDROGEN
LIGHT EMITTING DIODES
MICROWAVE RADIATION
PLASMA
SAPPHIRE
SCANNING ELECTRON MICROSCOPY
SEMICONDUCTOR LASERS
SEMICONDUCTOR MATERIALS
SILICON CHLORIDES
X-RAY DIFFRACTION