Etching of Mesa Structures in HgCdTe
Authors: Srivastav, V.; Pal, R.; Sharma, B.L.; Naik, A.; Rawal, D.S.; Gopal, V.; Vyas, H.P.
Source: Journal of Electronic Materials, Volume 34, Number 11, November 2005 , pp. 1440-1445(6)
Abstract:Mesa structures were etched in HgCdTe using different Br2/HBr/Ethylene glycol (EG) formulations. Etch rate and degree of anisotropy (A) were studied in detail for all of the combinations. Addition of EG to the conventional etchant gave A > 0.5, with controllable etch rates. Optimum etchant composition was determined to be 2% Br2 in a 3:1 mixture of EG:HBr. This composition resulted in a good anisotropy factor of ∼0.6 and a reasonably optimum etch rate of ∼2.5 m/min, with rms surface roughness of ∼2 nm. Kinetics of the etching reaction have also been studied for the optimum etchant concentration and an etching mechanism has been proposed.
Document Type: Regular Paper
Publication date: November 1, 2005