DOPING BEHAVIOR AND ELECTRICAL ACTIVATION OF CARBON IN GaAs

Heavily C-doped GaAs films, grown by metalorganic chemical vapor deposition with CCl₄ as external carbon source, have been studied by Hall-effect measurements, high-resolution double-crystal X-ray diffraction, and secondary-ion-mass spectroscopy (SIMS). Comparison among X-ray diffraction and Hall-effect measurements and SIMS results indicates that carbon is preferentially incorporated as acceptor on As lattice sites and electrical activation rate achieves 100%. There is no evidence of carbon incorporated on Ga sites as donors and incorporated on interstitial lattice sites.