Three chemical cleaning procedures for InSb(111) wafers were studied. X-ray
photoelectric spectroscopy, and scan electron microscope were used to assess
their credibility for use in manufacturing the InSb detectors. It is shown,
a suitable thermal treatment can remove In oxide and Sb oxide and therefore,
all procedures approach to similar results from this point of view. But
undulation and peel-like features has been observed on InSb(111) surface
etched by all etchants except a modified CP4A etchant
(HNO3:CH3COOH:HF:H2O at 2:1:1:10). Also control the etch rate
and etching process can be done better in CP4A than the others.
The XPS results show different spectra for SbOx and InOx when,
InSb(111) is compared with InSb(100) and it means that, for different
crystal orientation and different etchant there are different cleaning
method for removing SbOx and InOx.
Finally the effect of etchants on the performance of InSb detectors was
shown.