Implant isolation of both n-type InP and InGaAs by iron irradiation: Effect of post-implant annealing temperature

Abstract

1 MeV Fe/sub +/ was implanted into-n-type InP and InGaS layers at different substrate temperatures, -196/spl deg/C, room temperature (RT), 100/spl deg/C and 200/spl deg/C to obtain high resistivity regions. The sheet resistivity of the InP and InGaAs epilayers grown on semi-insulating (SI) InP substrates was measured as a function of substrates temperature and post-implantation annealing temperature (100-800/spl deg/C). For InP, a maximum sheet resistivity of /spl sim/ 1/spl times/10/sub 7/ /spl Omega///spl square/ was achieved for samples implanted at -196/spl deg/C, RT and 100/spl deg/C after annealing at 400/spl deg/C. For InGaAs samples, a Maximum sheet resistivity of 1/spl times/10/sub 7/ and 2.3/spl times/10/sub 6/ /spl Omega///spl square/ is obtained for -196/spl deg/C and RT implants respectively after annealing at 400/spl deg/C. For InGaAs samples, a maximum sheet resistivity of 1/spl times/10/sub 7/ and 2.3/spl times/10/sub 6/ /spl Omega///spl square/ is obtained for -196/spl deg/C and RT implants respectively after annealing at 50/spl deg/C for 60s. In both InP and InGaAs, the isolated regions exhibit good stability to heat treatment up to 500/spl deg/C for all cases irrespective of the irradiation temperature. The iron depth profile obtained by secondary ion mass spectrometry (SIMS) shows that iron does not diffuse up to an annealing temperature of 550/spl deg/C in both InP and InGaAs for all implantation temperatures. These results are novel since high sheet resistivity (/spl sim/5/spl times/10/sub 6/ /spl Omega///spl square/) is obtained in both InP and InGaAs samples implanted at -196/spl deg/C and RT, and annealed at 400/spl deg/C. These data demonstrate the potential usefulness of iron implantation for isolation of InP/InGaAs based devices.