Formation of low-resistivity region in p-Si substrate of SiGe/Si episystem by remote-hydrogen plasma treatment

We have studied effects of hydrogen treatment on the resistivity profile of the SiGe/Si episystem by spreading resistance (SR) method. In this paper, we present experimental findings that hydrogen treatment reduces the resistivity at a specific part in the Si substrate region. This position was confirmed to be under the interface between SiGe and Si that emerged on the bevel surface during hydrogen treatment. We investigated the depth of resistivity-reduced regions which was formed by various hydrogenating conditions and found that the region was extended to the same depth as the penetration depth of hydrogen. We concluded that the low-resistivity region was formed under the influence of hydrogen introduced from bevel surface. We attributed this resistivity reduction to formation of some defects which originally existed at the interface and diffused into Si substrate with hydrogen.