Range and standard deviation of ion-implanted Si in GaAs

Abstract

Carrier-concentration profiles of Si in semi-insulating GaAs have been obtained by C-V measurement techniques. Si + or Si + + ions were implanted at energies ranging from 50 to 600 keY, and annealing was carried out with Si3N4 encapsulants. Range parameters such as the projected range Xp and the projected standard deviation .:1Xp were experimentally determined by use of depths at the peak carrier concentration and at the live value of the peak carrier concentration of the profiles. It was found that .:1Xp was strongly dependent on the Cr contents of substrates while Xp was not. The measured carrier concentrations could be approximated by the Gaussian distribution, and values of Xp were in good agreement with the theoretical value of the projected range Rp. However, .:1Xp tended to saturate as the incident energies increased and deviated from the theoretical value of the projected standard deviation .:1Rp.