Title :
Feature size effects in Ar/Cl/sub 2/ chemically assisted ion beam etching of InP-based photonic crystals
Author :
Berrier, A. ; Mulot, M. ; Talneau, A. ; Anand, S.
Author_Institution :
Dept. of Microelectronics & Information Technol., R. Inst. of Technol., Kista
Abstract :
This work addresses feature size effects (the lag-effect and roughness development) in chemically assisted ion beam etching (CAIBE) etching of InP-based photonic crystals. Photonic crystal fields with varying hole size and periods were etched with different etching times. The slope of the etch depth versus diameter curves (lag-curves) reveals an aspect-ratio dependence, with an etch limiting aspect ratio of the order of 25. A model of the etch rate specific to Ar/Cl2 CAIBE is proposed. We calculate the etch rate using a physico-chemical model which takes in to account the effect of Ar-ion sputtering and surface chemical reactions. In addition, it combines the aspect ratio dependence of the gas conductance of the etched holes. Finally, the bottom roughness of the etched holes is examined; its origin and evolution are discussed
Keywords :
III-V semiconductors; indium compounds; photonic crystals; sputter etching; surface chemistry; surface roughness; Ar-ion sputtering; InP-based photonic crystals; bottom roughness; chemically assisted ion beam etching; etch depth; etch limiting aspect ratio; feature size effects; gas conductance; lag-effect; photonic crystal field; physico-chemical model; roughness development; surface chemical reactions; Chemical technology; Dry etching; Ion beams; Optical losses; Photonic crystals; Resists; Semiconductor materials; Shape; Sputter etching; Sputtering;
Conference_Titel :
Indium Phosphide and Related Materials Conference Proceedings, 2006 International Conference on
Conference_Location :
Princeton, NJ
Print_ISBN :
0-7803-9558-1
DOI :
10.1109/ICIPRM.2006.1634185
