A study of Zn diffusion in InP at low temperature

The diffusion of Zn in InP at low temperature is investigated. The experiment is accomplished in an evacuated and sealed quartz ampoule using Zn_eP₂ as the source of Zn. The electrical characteristics of the diffusion samples obtained by the isotemperature process and the two-temperature process have been compared. It is found that with the two-temperature process one can obtain a smooth, damageless and high-concentration surface layer. This process has been applied to fabricate InGaAsP/InP light emitting diodes, and the diodes obtained have an output power of ≥1mW with a series resistance of 2–5Ω. The behaviors of Zn diffusion in InP are discussed.