Reduction of surface defects on the GaP window layer of 630Â nm AlGaInP LED using post-Zn diffusion process

► GaP window layer surface improved by the post-Zn diffusion for 630 nm AlGaInP LED. ► GaP window layer resistance decreased and hole concentration increased by the post-Zn diffusion. ► GaP window layer surface doping concentrations increased by the post-Zn diffusion. ► GaP window layer surface defects reduction is important for AlGaInP LED efficiency.