Electrical properties of Hg1−xCdxTe by different etching techniques

Effects on the electrical properties of HgCdTe photoconductive devices etched by inductively coupled plasma (ICP) based on CH4-Ar mixture, ion beam milling (IBM) and bromine-hydrogen bromide solution (Br2/HBr) have been investigated. Magnetic-field-dependent Hall measurement and optoelectronic performance measurement at liquid nitrogen temperature were performed. Mobility spectrum analysis (MSA) and multicarrier fitting (MCF) were applied to evaluate the carrier characteristics. Sample etched by ICP indicated a higher mobility and the carrier scattering mechanism was dominated by polar optical phonon (POP) which could lead to superior detector performance accordingly. Meanwhile, sample etched by IBM was found to have large amount of electron concentration and sample etched by Br2/HBr showed a very low mobility. The dominant mechanism of Br2/HBr etched sample was ionized impurity scattering for the carriers which meant inferior resultant detector performance.