Fabrication of overpass microstructures in GaAs using isotropic reactive ion etching

Journal Article · · Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena; (United States)

DOI:https://doi.org/10.1116/1.586043· OSTI ID:6350713

Hur, K Y; Compton, R C ^[1]

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1. Cornell Univ., Ithaca, NY (United States)

Plasma etching allows uniform and repeatable etching of semiconductors used in electronics, optoelectronics, and micromechanics applications. Reactive ion etching (RIE), in particular, is capable of producing high-resolution pattern transfer of submicron feature sizes as small as 20 nm in GaAs. In RIE of III-V semiconductors, a mixture of chlorine and inert gas is often used. The resulting etch is usually highly selective, anisotropic and independent of substrate crystal orientation. Such etches are characterized by vertical walls with well controlled widths and depths. Decreasing the fraction of inert gas increases the percentage of reactive species and more lateral etching occurs. Hu et al. has observed increased undercut profiles in GaAs as the ratio of chlorine to argon is increased. As is discussed in this communication, chamber pressures and species can be optimized to considerably enhance the lateral etch rate. This process allows isotropic etches that are traditionally performed with wet chemistry to be done with RIE in a well controlled fashion. As a demonstration of this approach, a series of overpass structures, in which the supporting substrate material is removed, are shown. 12 refs., 3 figs.

• OSTI ID: 6350713
• Journal Information: Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena; (United States), Journal Name: Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena; (United States) Vol. 10:6; ISSN 0734-211X; ISSN JVTBD9
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation & Manufacture
360602 -- Other Materials-- Structure & Phase Studies
ARSENIC COMPOUNDS
ARSENIDES
BEAMS
ETCHING
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
ION BEAMS
MICROSTRUCTURE
MORPHOLOGY
PNICTIDES
SURFACE FINISHING
SURFACE PROPERTIES
SURFACES