ELECTRONIC-PROPERTIES OF ARSENIC-DOPED GALLIUM NITRIDE

Arsenic-doped GaN films were grown via metalorganic chemical vapor dep osition using trimethylgallium, ammonia, and arsine precursors. The ar senic concentration increases from 3X10(16) to 5X10(17) cm(-3) in resp onse to a change in arsine mole fraction from 3.3X10(2) to 3.2 X 10(4) ppm. The electron mobility increases with arsenic content reaching a maximum value of 374 cm(2)/V s at 300 K. In addition, the integrated p hotoluminescence intensity exhibits a 35-fold increase in magnitude at 300 K. To explain these findings, a simple physical model is proposed in which arsenic ''impurities'' occupy otherwise vacant sites on both the gallium and nitrogen sublattices. (C) 1998 American Institute of Physics.