Band offsets of InGaP/GaAs heterojunctions by scanning tunneling spectroscopy
نویسندگان
چکیده
Scanning tunneling microscopy and spectroscopy are used to study InGaP/GaAs heterojunctions with InGaAs-like interfaces. Band offsets are probed using conductance spectra, with tip-induced band bending accounted for using 3-dimensional electrostatic potential simulations together with a planar computation of the tunnel current. Curve fitting of theory to experiment is performed. Using an InGaP band gap of 1.90 eV, appropriate to the disordered InGaP alloy, a valence band offset of eV 01 . 0 38 . 0 ± is deduced along with the corresponding conduction band offset of eV 01 . 0 10 . 0 ± (type I band alignment).
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