SEMICONDUCTOR DEVICE HAVING SOI STRUCTURE AND METHOD FOR MANUFACTURING THE DEVICE

摘要

A semiconductor device having such an SOI structure that diffusion of impurities from the source/drain regions into the end portions of a silicon layer below the gate electrode is prevented. In this semiconductor device, nitrogen (8) is introduced into at least one of the source/drain regions (14) and the end portions of the semiconductor layer (3). A first concentration peak of the nitrogen concentration profile is at least in one of the end portions of the regions (14) in the direction where the electrode (12) extends and the end portions of the layer (3). Because of the nitrogen concentration profile, point defects, etc., which mediate the diffusion of impurities are trapped, and consequently the diffusion of impurities from the regions (14) is suppressed. Therefore, abnormal leakage current, etc., are prevented.