抄録
A reaction model is discussed for in-situ boron-doped silicon chemical vapor deposition that uses Si2H6 and B2H6. First, the elementary reactions were studied by using an ab initio molecular orbital method and the first-principle molecular dynamics method. These showed that the B2H6 decomposes into BH3 easily and that BH3 has a high probability of sticking to silicon film. Therefore, the boron was doped in the silicon film by BH3. The desorption energy of H2 terminated silicon film surface was lower due to the boron doping in the silicon film. Then, an increase in the boron concentration of the silicon film increased the sticking probability of the Si2H6. Next, a deposition model was made on the basis of these results, and reaction constants were determined by using experimental results. Finally film thickness distribution was simulated by using a flow-diffusion-reaction analysis and an integrated method on the above deposition model. The result shows that our reaction model can replicate experimental step coverage.
