Phosphorus diffusion in germanium following implantation and excimer laser annealing

Abstract

We focus our study on phosphorus diffusion in ion-implanted germanium after excimer laser annealing (ELA). An analytical model of laser annealing process is developed to predict the temperature profile and the melted depth in Ge. Based on the heat calculation of ELA, a phosphorus diffusion model has been proposed to predict the dopant profiles in Ge after ELA and fit SIMS profiles perfectly. A comparison between the current–voltage characteristics of Ge n+/p junctions formed by ELA at 250mJ/cm2 and rapid thermal annealing at 650°C for 15s has been made, suggesting that ELA is promising for high performance Ge n+/p junctions.