1 February 1992 Chemically assisted ion beam etching of GaAs and GaSb using reactive flux of iodine and Ar+ beam
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Proceedings Volume 1593, Dry Etch Technology; (1992) https://doi.org/10.1117/12.56924
Event: Microelectronic Processing Integration, 1991, San Jose, CA, United States
The paper discusses a Chemically Assisted Ion Beam Etching (CAIBE) technique for etching of GaAs and GaSb based on reactive flux of iodine vapours derived from elemental iodine and Ar+ ion beam. The effect of iodine partial pressure in the range 0-14x10-5 torr has been studied on the etch rate of GaAs and GaSb at three different ion beam current densities. Initially, the etch rate increases with increase in iodine partial pressure; but at higher iodine flux the etch rate tends to attain saturation value. The Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) results show that uniform etching is obtained but at higher current density and high iodine flux etch pits start appearing. The high resolution electron microscopy (HREM) and electron diffraction studies show that no crystalline defects are introduced during Ar+/I2 CAIBE. The energy despersive analysis (EDS) of etched surface does not show presence of iodine. Thus the technique gives higher etch rate in comparison to only Ar+ ion beam without any art effect in terms of crystalline structure or surface contamination. The technique has been successfully used for anisotropic etching of 1.5 um test patterns using Dynachem OFPR-800 positive resit and for preparation of TEM specimen. The results on GaAs and GaSb are compared with those of Si, InP and InSb etching using Ar+/I2 CAIBE. A possible etch mechanism has been proposed to explain the etch behaviour.
© (1992) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Lalit M. Bharadwaj, Lalit M. Bharadwaj, P. Bonhomme, P. Bonhomme, J. Faure, J. Faure, G. Balossier, G. Balossier, Ram P. Bajpai, Ram P. Bajpai, "Chemically assisted ion beam etching of GaAs and GaSb using reactive flux of iodine and Ar+ beam", Proc. SPIE 1593, Dry Etch Technology, (1 February 1992); doi: 10.1117/12.56924; https://doi.org/10.1117/12.56924

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