Non-Planar Substrate Metal-Oxide-Semiconductor Photo-Capacitance Detectors with Enhanced Deep Depletion Sensitivity at Convex Corner

摘要

Non-planar substrate metal-oxide-semiconductor (MOS) photo-capacitance detector with enhanced deep depletion (DD) at convex corner was demonstrated. The expansion-shrinkage mechanism of depletion width due to illumination was adopted. For non-planar substrate MOS devices, the enhanced photo-capacitance sensitivity in deep depletion region is caused by the large variation of depletion width at convex corners. The smaller area device shows lager photo-capacitance sensitivity due to the shorter distance between the edge of illumination and the convex corner. The significant enhanced photo-capacitance variation sensitivity (AC/C) of 85.5% was achieved for non-planar MOS device with an EOT of 2.8 nm in the smallest area of 160 × 160 μm~2 which respect to that of 7% for planar one under the same illumination intensity of 90 mW/cm~2.