Abstract
Anomalous capacitance‐voltage (CV) characteristics of BF2‐implanted p+‐polycrystalline silicon (polysilicon) gate metal‐oxide‐semiconductor (MOS) structures annealed by rapid thermal annealing (RTA) are reported for the first time. It is found that both high‐frequency and quasi‐static CV curves exhibit an increased capacitance at the depletion and weak inversion regions, which increases with p+‐polysilicon RTA drive‐in durations. The quasi‐static CV curves show a gate bias dependence of the inversion capacitance which shows a distorted ‘‘plateau’’ (i.e., reduced inversion capacitance for a very narrow gate voltage range) in the strong inversion regions. These anomalous CV characteristics are believed to be due to the penetrated B‐F complexes which act as interface state and deep level defect centers.