Structural and electrical contact properties of LPE grown GaAs doped with indium |
| |
Authors: | J F Chen C R Wie |
| |
Affiliation: | (1) Dept. of Electrical and Computer Engineering, State University of New York at Buffalo, 201 Bonner Hall, 14260 Amherst, NY |
| |
Abstract: | We have studied the effects of In doping on the structural and electrical properties of a liquid phase epitaxially (LPE) grown
GaAs. The results of surface morphology studies show that macroscopically, a terrace-free area in certain regions can be seen
on the surface of a GaAs layer doped with In of 2.4 × 1019 cm3. The full widths at half-maximum (FWHM) of x-ray double crystal rocking curves show that a GaAs epi-layer of good crystalline
quality can be obtained by doping In to a concentration up to 4.3 × 1019 cm-3, beyond which a sharp increase in the FWHM is observed. Etch pit density (EPD) study also shows that the dislocation density
is reduced by doping the epi-layer with In. At an optimum In concentration, 2.4 × 1019 cm-3, the EPD was reduced by a factor of 20 when measured at the surface of a 9μm thick epi-layer. The I-V characteristics of Au-GaAs Schottky diodes show, for the layer with an optimal In concentration,
an ideality factor close to 1.04 over more than seven decades of current. For the same layer, the reverse I-V characteristics
are close to an ideal Schottky diode and could be fitted by a theoretical curve, combining the thermionic field emission and
thermionic emission. For doping levels higher than 6 × 1019 cm-3, the epitaxial layer quality deteriorated. We report the results obtained from the Nomarski optical microscope, double crystal
x-ray rocking curves, etch pit density, forward and reverse I-V characteristics, and the theoretical current transport models. |
| |
Keywords: | Isoelectronic doping liquid phase epitaxy dislocation electrical I-V |
本文献已被 SpringerLink 等数据库收录! |
|