Investigation of the two-dimensional electron gas in HgCdTe by quantum Hall effect measurements

Abstract

By means of the first observations of the quantum Hall effect in a type II–VI semiconducting compound, Hg1−xCdxTe, we have studied the two-dimensional electron gas formed by the inversion layer of a MISFET (metal–insulator–semiconductor field effect transistor) device. Extensive details regarding the fabrication and use of the MISFET are described. The data also indicate an abrupt onset of the quantum Hall effect which, when interpreted with a percolation threshold theory, is used to further investigate conditions affecting charge transport mechanisms in the two-dimensional electron gas at a HgCdTe interface.

Methods for magnetotransport characterization of IR detector materials

“…This occurs because G~~ has no dependence on B whenever the Fermi level passes through a gap between Landau levels [78] (states in the gaps are defect-broadened tail states, which have no conduction at low 0. Kirk et al [79] and Siman [SO] for Hg, -,Cd,Te metal-insulator-semiconductor (MIS) structures with quasi-2D electron gases at the surface (Nw = 1). Quantized Hall conductance has also been observed in HgTe-CdTe heterostructures, both in multiple quantum wells (which may be thought of as .Vw quasi-2D populations conducting in parallel) and in superlattices with relatively strong 3D dispersion [Sl] (a superlattice can also display energy gaps containing only localized states if the Landau level spacing is larger thaz &c mhiband width [82]).…”

Investigation of iodine as a donor in MBE grown Hg1−xCdxTe

“…The data at 4.2K of one sample (Q1099) is shown in Fig. Prior to the present investigation the quantum Hall effect for Hg 1-x Cd x Te has been reported in HgTe-CdTe superlattices, 10 in a Hg 1-x Cd x Te metal-insulator-semiconductor field effect transistor device 11 and in Hg l-x Cd x Te bicrystals 12 but to our knowledge not for single HgTe quantum wells. Some samples could only be measured under illumination with a red light emitting diode.…”

Improved characterization and evaluation measurements for HgCdTe detector materials, processes, and devices used on the GOES and TIROS satelites

“…Measurements of noise and dark spectroscopy, the observation of subbands due to inversion layer quantization effects, has been reported using gated diodes and misfets[107, 108]. misfets have been used as a test structure for the quantum Hall effect[139] and magnetotransport measurements[107]. By changing the gate voltage on an HgCdTe misfet, the magnetotransport of the two-dimensional electron gas has been modulated from classical free electron behaviour primarily by their resistance, which can be divided into components due to the semiconductor and to the contact resistance.…”