MBE growth of near-infrared InGaAs photodetectors with carbon tetrabromide as a p-type dopant

The carbon doping of In_xGa_1-xAs was systematically studied as a function of carbon tetrabromide flux and indium molar fraction. The efficiency of carbon incorporation in InGaAs lattice matched with InP was the same as GaAs and showed a maximum attainable doping level of 2×10²⁰Cm^-3. The increase of indium molar fraction showed autocompensation and a switch of conductivity from p-to-n-type, at an In molar fraction of 80%. In_0.73Ga_0.27As photodetectors were fabricated using carbon as a dopant. The figures of merit of the p-i-n photodetectors showed parameters close to those of beryllium doped devices. CBr₄ can be used as an effective p-type doping precursor in solid-source molecular beam epitaxy in In_xGa_1-xAs with indium molar fraction up to 80%