Paper Title
Growth and Characterization of InSe/Ge/InSe Interfaces
Abstract
In the current study, we report the effect of insertion of a 200 nm thick Ge film between two layers of InSe. The
Ge sandwiched InSe films are studied by means of X-ray diffraction technique, energy dispersion X-ray spectroscopy
attached to a scanning electron microscope, optical spectrophotometry and light power dependent photoconductivity. It was
observed that, The InSe prefers the growth of InSemonophase when deposited onto glass and the growth of −In2Se3 when
deposited onto InSe/Ge substrate. The three layers interface (InSe/Ge/ −In2Se3) exhibits a Ge induced crystallization
process at annealing temperature of 200 oC. The optical analysis has shown that the InSe films exhibit a redshift upon Ge
sandwiching. In addition, the conduction and valence bands offsets at the first interface (InSe/Ge) and at the second
(Ge/ −In2Se3 ) interface are found to be 0.55 eV and 1.0 eV, and 0.40 eV and 1.38 eV, respectively. Moreover, the
photocurrent of the Ge sandwiched InSe exhibited higher photocurrent values as compared to those of InSe. On the other
hand, the dielectric spectral analysis and modeling which lead to the identifying of the optical conduction parameters
presented by the plasmon frequency, electron scattering time, free electron density and drift mobility have shown that the
Ge sandwiching increased the drift mobility values from 10 cm2/Vs to ~42 cm2/Vs. The main plasmon frequency also
increased from 1.08 to 1.68 GHz.
Keyword - InSe; Nanosandwich; Dielectric ; Terahertz ; Plasmon Devices; Ge Sandwiching