DOPING CHARACTERISTICS AND ELECTRICAL-PROPERTIES OF MG-DOPED ALGAN GROWN BY ATMOSPHERIC-PRESSURE MOCVD

Doping characteristics and electrical properties have been studied for Mg-doped AlxGa1 - xN grown by atmospheric pressure MOCVD, using Cp2Mg . The net acceptor concentration increased with increasing [Cp2Mg]/[II I] and saturated at about 7 x 10(18) cm(-3) for x = 0.15, while the Mg concentration did not saturate up to 5 x 10(19) cm(-3). Both of them were rather small than those of GaN, although they gradually increased with increasing Al mole fraction. The hole concentration as high as 6 .6 x 10(16) cm(-3) was obtained and the hole thermal activation energy (Delta E-A) has been estimated to be about 250 meV for x = 0.15 from the relation between the net acceptor concentration and the hole conce ntration at room temperature. The electrical resistivity increased wit h increasing x, and the value, 15 Ohm cm, for x = 0.15 was considerabl y higher than that for GaN (similar to 2 Ohm cm). (C) 1998 Elsevier Sc ience B.V. All rights reserved.