Minority carrier lifetime in MOCVD-grown C- and Zn-doped InGaAs

Abstract

Heavily C-doped p-type InGaAs has been successfully grown by metalorganic chemical vapor deposition using CBr/sub 4/ as a C precursor. A doping concentration as high as 2/spl times/10/sup 19/ cm/sup -3/ has been reached for as-grown (non-annealed) samples. Photoluminescence measurements have been employed to obtain and compare the non-radiative lifetimes in C- and Zn-doped InGaAs. The minority carrier lifetime of as-grown InGaAs:C samples is significantly lower than for as-grown InGaAs:Zn for the same doping concentration. Carrier lifetimes range from 373 ps (p=6.6/spl times/10/sup 16/ cm/sup -3/) to 1.5 ps (p=2.3/spl times/10/sup 19/ cm/sup -3/) in as-grown InGaAs:C, and from 6.8 ns (p=5.0/spl times/10/sup 16/ cm/sup -3/) to 16.8 ps (p=2.1/spl times/10/sup 19/ cm/sup -3/) in InGaAs:Zn, respectively. InGaAs:Zn grown at the same low temperature (450/spl deg/C) as InGaAs:C has a higher minority carrier lifetime. The minority carrier lifetime difference between InGaAs:Zn and InGaAs:C samples is attributed to lower V/III ratio and hydrogen passivation, as well as, lower growth temperatures for the carbon doped InGaAs samples.