Formation mechanism of Pt-H complexes in Pt doped Si by chemical etching

摘要

The formation mechanism of platinum-hydrogen (Pt-H) complexes introduced by hydrogen injection into Pt-doped n-type Si wafers during wet-chemical etching is elucidated taking the influence of phosphorous (P) into consideration. Using deep-level transient spectroscopy (DLTS) depth profiling and capacitance-voltage analysis, the concentration profiles of Pt-H complex and P-H pair in Pt-undiffused and diffused n-type Si are measured for various etching rates, etching temperatures, and P and Pt concentrations, Moreover, to examine the influence of the space charge layer formed near the surface on the formation of P-H pair, P-H pair concentration profiles are compared with boron-hydrogen (B-H) ones in B doped p-type Si wafers, in which B is negatively charged in the space charge layer, contrary to positively charged P, From these results, it is clarified that the formations of Pr-H complexes and P-H pair are mainly dominated by the electric field in the space charge layer formed by positive P ions.