RELATIONSHIP BETWEEN IMPLANTATION DAMAGE AND ELECTRICAL ACTIVATION INGALLIUM-ARSENIDE IMPLANTED WITH SI+

The relationship between implantation damage and electrical activation has been investigated in GaAs implanted with 100-keV Si-30+ to doses of 5X10(13)/CM2 and 2X10(14)/CM2, using low and moderate beam currents at room temperature (RT) and at slightly elevated temperatures. For a given Si+ dose, the damage, measured by ion channeling immediately af ter implantation, was varied by more than a factor of 2 over the range of conditions studied. A strong negative correlation was established between this damage and the electrical activation obtained after high- temperature annealing, i.e., an increase in the initial damage led to a decrease in the sheet-carrier concentration. Tle results demonstrate a scheme for increasing the sheet-carrier concentration beyond that t ypically obtained for high-dose Si in GaAs, namely, by using a slightl y elevated implant temperature (approximately 90-degrees-C for a beam current of 1 muA/cm2). In addition, the initial damage is shown to con sist of two components; one that is stable at RT and another that is n ot. The sheet-carrier concentration was found to be affected only by t hat component of the damage that is stable at RT, although both compon ents were reduced by increasing the implant temperature or by reducing the dose rate.