Shallow ohmic contact to both n- and p-GaAs

Publisher Website
Google Scholar
Abstract
A shallow Pd/Ge/Ti/Pt/ohmic contact for both n‐ and p‐GaAs has been investigated. The contacts were rapid thermally annealed in N2 for 15 s at temperatures from 350 to 550 °C. The lowest average specific contact resistances were 4.7×10−7 and 6.4×10−7 Ω cm2 for the n‐ and p‐GaAs, respectively, when the n‐GaAs was doped with Si to 2×1018 cm−3 and the p‐GaAs was doped with carbon to 5×1019 cm−3. Electrical measurements and Auger depth profiles showed that the contacts were stable as they remained ohmic after an anneal at 300 °C for 20 h for both n‐ and p‐GaAs. The p contact is more stable than the n contact at the higher temperatures where there is more As outdiffusion as determined by Auger depth profiles. Transmission electron microscopy showed that the interfaces between the p‐GaAs and the contacts were smooth for both as‐grown and annealed samples, and no oxides were detected.

This publication has 13 references indexed in Scilit: