Elimination of the kink effect in GaAs metal semiconductor field-effect transistors by utilizing a low-temperature-grown buffer layer

Abstract

GaAs metal semiconductor field-effect-transistors (MESFETs) utilizing a nondoped GaAs buffer layer grown by molecular beam epitaxy at 300 °C do not show the kink effect which is observed in GaAs MESFETs utilizing a nondoped GaAs buffer layer grown at 600 °C. However, in both types of FETs, almost the same photoemissions caused by drain avalanche multiplication, are observed between the gate and the drain. A deep level transient spectroscopy (DLTS) spectrum shows that the low-temperature buffer (LTB) layer contains a deep level similar to the EL-2 level with high density. The kink effect may be eliminated because the deep level works as a large recombination center for holes generated by drain avalanche multiplication.

Structural and defect characterization of GaAs and AlxGa1−xAs grown at low temperature by molecular beam epitaxy

“…Over the last several years considerable interest has been shown in GaAs layers grown by molecular beam epitaxy ͑MBE͒ at low substrate temperatures ͑200-300°C͒. [1][2][3][4][5][6][7][8] Although the growth of low-temperature GaAs ͑LT-GaAs͒ was first reported by Murotani et al in 1978, 9 this interest stems, to a large extent, from a 1988 paper by Smith et al 10 Whereas the former work suggested that LT-GaAs might find use as a highly resistive buffer layer for GaAs integrated circuits, it was the latter study that demonstrated that backgating could be eliminated by inserting a LT layer between the device and the substrate. However, LT-GaAs is also interesting from a purely scientific standpoint.…”

Above band gap absorption spectra of the arsenic antisite defect in low temperature grown GaAs and AlGaAs

“…These similarities were confirmed by comparing various other properties of the EL2 defect and LT-GaAs defects using a variety of experimental techniques. 9,10 Certain deviations of conformity in those spectra have been explained by local strain in LT-GaAs. 4 Taking these strain effects into account, it seems reasonable to call at least a certain part of the defects in LT-GaAs.…”