Lithium diffusion profile onto highly resistive p-type silicon

In this work, the effect of temperature and time of diffusion on the lithium (Li) profile into p-type highly resistive silicon have been investigated. The high-purity Li metal (99.995%) was deposited onto p-type (1 1 1) silicon surface and thermally diffused into the bulk at a 2×10−6 Torr vacuum pressure. The four-probes technique was used to determine the diffusion profile of Li impurities into silicon. Scanning electron microscopy (SEM) was used to measure the diffused junction depth (Xj). The Li diffusion constant DLi was then extracted using the measured surface concentration NLi. Thus, the variation of DLi as a function of diffusion temperature was determined. Simulated profiles was obtained by means PC1D calculate tool. A good agreement was found when the simulated and experimental results were compared with those of the literature values.