Low temperature processing of nanostructures based on II-VI semiconductors quantum wells

Abstract

We report the -rst results of electron beam lithography processes performed on polymethyl methacrylate (PMMA) and hydrogen silsesquioxane (HSQ) resists, which have been pre-backed in vacuum at T ≤ 90 °C. For such low temperature processing the lithographical resolution is reduced as compared to standard procedures, however, the exposure contrast and adhesion to CdTe and HgTe substrates have been su-cient for the fabrication of sub-μm quantum devices. Furthermore, the new method of electrical microcontact forming is proposed, based on the local melting and annealing of an indium metal layer, performed with the application of accelerated electron beam. The method has been tested for CdTe/CdMgTe quantum wells using the lithography techniques, the exposure parameters have been optimized by inspecting the morphology of annealed metal film via the in situ imaging.