Quantitative study of carbon doping of GaAs grown by metalorganic vapor-phase epitaxy

Based on the analysis of experimental data from the atmospheric-pressure-me talorganic vapor-phase epitaxy (APMOVPE) of carbon-doped GaAs, using trimet hylgallium (TMGa) and arsine (AsH3) as growth precursors and carbon tetrach loride (CCl4) as dopant precursor, the quantitative relation between contro l parameters, namely growth temperature and flow rates of CCl4 and AsH3, an d hole concentration has been investigated and established, which is p = 5 x 10(8)F(CCl4) F(AsH3)(-1.5)exp(2 x 10(5)/RTg), with the flow rate of TMGa kept constant at 0.78 SCCM. Since this deduction was fully based on the exp erimental data obtained, the result can well demonstrate the existing dopin g characteristics, and also agree with the scattered individual expressions previously reported. Finally, an improved CCl4-doping mechanism for the MO VPE growth of GaAs has been presented. (C) 2000 Elsevier Science B.V. All r ights reserved. PACS. 81.15.Gh: 68.55.Ln.