Shallow defect etching of GaAs using AB solution under laser illumination

Abstract

A defect etch procedure for GaAs 〈100〉 oriented surfaces was developed. I and Buiocchi etch, used under laser (λ = 6328 å) illumination. A comparison of etch patterns obtained with the original AB etch under white light illumination, and those obtained with the procedure developed shows that, in addition to some practical advantages, the latter allows good contrast patterns to be revealed with a tenfold reduction of the etch depth (0.2–0.5 μm), while retaining all the interesting features of the Abrahams and Buiocchi solution. The procedure should therefore be of particular value in the study of thin GaAs epitaxial layers.