Dislocation behavior of surface-oxygen-concentration controlled Si wafers

We have investigated dislocation behavior in the surface area of surface-oxygen-concentration controlled Si wafers treated by a high temperature rapid thermal oxidation (HT-RTO). The HT-RTO process allows us to precisely control the interstitial oxygen concentration ([Oi]) in the surface area of the Si wafers. Sizes of rosette patterns, generated by nano-indentation and subsequent thermal annealing at 900 °C for 1 h, were measured for the Si wafers with various [Oi]. It was found that the rosette size decreases in proportion to the − 0.25 power of [Oi] in the surface area of the Si wafers, which were higher than [Oi] of 1 × 1017 atoms/cm3. On the other hand, [Oi] of lower than 1 × 1017 atoms/cm3 did not affect the rosette size very much. These experimental results demonstrate the ability of the HT-RTO process to suppress the dislocation movements in the surface area of the Si wafer.