Interstitial Chromium in Silicon on the Micron Scale

Imaging the Photoluminescence (PL) intensities related to recombination via the two metastable states of chromium in boron doped silicon is a highly sensitive means for measuring the spatially resolved interstitial chromium concentration ([Cri]) in silicon. In this work we show that the straightforward combination of this method with a micro PL Spectroscopy (μPLS) setup allows for the detection of [Cri] with micrometre resolution. Measurements performed on a chromium contaminated multicrystalline (mc) silicon wafer show impurity inhomogeneity on the micron scale, yielding a proof of principle and revealing new insight into chromium concentration variations around defects.