Optimum proton energy for DH lasers determined by in situ monitoring during bombardment

A special laser structure has permitted in situ measurements of laser threshold currents, junction voltages, and capacitances to be made during the actual implantation of protons. Of these three parameters, the device capacitance proved to be the most sensitive in providing information about the effect of implants in the vicinity of the p-n junction. It is found that the principal laser properties are determined not by those protons near the peak of the implanted distribution, but by those protons in the leading edge of the distribution at effective concentrations two or three orders of magnitude lower than at the peak. The optimum implantation energy places the peak of the distribution at
0.8-0.9 \mu
m from the p-n junction.