Semiconductor device with p=n junction, e.g n=channel transistor - has impurity diffusion region between first impurity region and impurity concentration peak

摘要

The semiconductor device includes an oxide film (13) formed on the upper surface of a p-type silicon substrate for isolating an device region (50). A p-type impurity-diffusion region (5) extends from the vicinity of the lower surface of the oxide film to a position at a defined depth into the device region. The impurity diffusion region has an impurity atom concentration peak. An n+ impurity diffusion region (9) is formed on the p-type substrate in the device region next to the oxide film. An n- impurity diffusion region (1) is formed between the n+ region (9) and the p-type impurity diffusion region (5). ADVANTAGE - Improved electrical reliability, increased current drive, reduced leakage current.