Abstract
The influence of temperature treatment on the p-doping concentrations near the interfaces of an InP/InGaAsP heterostructure has been investigated. During this treatment a significant out-diffusion of Zn from the p-InP layer into the adjacent InGaAsP layers took place. Due to different segregation coefficients of Zn in InP and InGaAsP an out-diffusion of Zn from the InP into the InGaAsP layer also occurred when the p-doping in InP is lower than in InGaAsP. In InP/InGaAsP lasers such an out-diffusion of Zn into the active InGaAsP layer usually leads to enhanced threshold currents.