Abstract
The characteristics of an amorphous GaAs film by implanting dense arsenic ions into semi-insulating GaAs substrate have been studied. The specific contact resistance of the sample at room temperature is found to be 1.1×10 -1 Ω cm 2 . This indicates that the conduction-band electron concentration is less than 10 13 cm -3 . The activation energy at temperature above 360 K and the density of states are, respectively, 0.6 eV and 10 27 m -3 eV -1 as estimated from the slope of Arrhenius plot. Fitting of the Arrhenius plot also suggests that the carrier transport at metal/semiconductor junction of this material below 360 K is dominated by the variable-range hopping conduction mechanism which depends on deep level defects. © 1994 American Institute of Physics.