Comparison of two kinds of oxygen donors in silicon by resistivity measurements

Abstract

Donor formation during heat treatment of silicon in the 550–800 °C temperature range has been investigated by resistivity measurements. The maximum donor concentration obtained here is about 1×1016/cm3 in p-type Czochralski-grown silicon. The donor is confirmed to be correlated with oxygen impurity as is the ’’thermal donor’’ formed in 300–500 °C annealing. The new donor, however, differs greatly in annealing behavior from the thermal donor. Preannealing at 470–550 °C and/or high carbon concentration promote the new donor generation at 650 °C annealing. A two-step reaction is proposed to interpret the donor-formation mechanism.