Formation of Shallow n-p Junctions in Cz-Si by Low-Energy Implantation of Carbon Ions

摘要

A low-temperature method for shallow n-p junction formation in thin subsurface layers of p-type Cz-Si wafers is presented. Junctions are formed due to the enhanced formation of thermal donor centers by C ion implantation. It is shown that by C ion implantation with doses between 0.6 and 1.0×10~(14) cm~(-2) and subsequent annealing at temperatures in the range between 600 and 650 ℃, n-p junctions with breakdown voltages of 100 to 150 V and reverse currents below 1×10~(-10) A at 20 V bias, can be formed. The highest breakdown voltages and lowest leakage currents were obtained for a C ion implantation dose of 1×10~(14) cm~(-2) and for annealing at 600 ℃.