Photoacoustic and photoluminescence studies of H⁺ ion‐implanted n‐GaAs

Abstract

The surface of silicon‐doped GaAs (100) grown by the vertical Bridgman method has been implanted with H+ ions at 30 keV for various doses from 1014 to 1017 cm–2 and studied using photoacoustic and photoluminescence spectroscopy to understand the effects of hydrogen ion implantation on GaAs:Si. The results are compared with Raman measurements. All the measurements confirm the sign change of charge carriers at a dose of 1015 cm–2. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

EPR and photoacoustic studies on 30kev H+ ion-implanted n-GaAs

“…The similarity in the behavior of the PA and PL [4] to that of the EPR signals very clearly demonstrate that there is a change at 10 15 cm À2 dosage. The minimum in g-value at 10 15 cm À2 dosage may be understood as a change in the polarity of charge carriers at this dosage due to change in environment, because EPR has not identified any other defect.…”

“…It has already been discussed in our earlier papers [2,4] that H + ion implantation of n-GaAs would change it into p-GaAs for a particular dosage. This ion implantation passivates the free electron at low doses and at fairly high doses it produces defect complexes, which release holes to convert n-to p-type.…”

“…Various studies on defects in n-GaAs are reported in literature [1][2][3][4] for H + ion implantation. Dharmarasu et al [1], from the Raman results of H + and He + -implanted crystalline n-GaAs (with carrier concentration o4.2 Â 10 17 cm À3 ) reported lattice damages at higher doses.…”

“…In our earlier paper [4], effect of 30 keV H + ion implantation (doses 10 14 to 10 17 cm À2 ) on n-GaAs was studied by photoacoustic (PA) and photoluminescence (PL) measurements. It was observed that there is a type conversion at a dose of 10 15 cm À2 from n-to p-type.…”

“…The PA spectra [4] were recorded as a function of the wavelength of the incident beam (350-1100 nm) for constant modulation frequency for as-grown and H + ion-implanted samples for various doses from 10 14 to 10 17 cm À2 . The spectra were normalized using the PA signals from carbon black.…”