Single step implant isolation of p/sup +/-InP using MeV ion beams

Implant isolation of epitaxial p/sup +/-InP layers using a single, high-energy O implant, with a projected range several times that of the conductive layer, has been investigated. Results are compared with two alternative implant isolation schemes, with ion ranges confined to the epitaxial layer: a multiple, low-energy O implant and a single, high-energy In implant. Single-step implant isolation offers considerable process simplification compared to conventional, multiple-implant sequences. Comparable sheet resistance values were achieved for the three different implant sequences, though the two schemes with ion ranges confined to the conductive layer yielded greater thermal stability. This difference is attributed to implantation-induced conduction in the semi-insulating substrate following the high-energy O implant.<>