| 摘要 |
PURPOSE:To obtain an MIS semiconductor device having quick switching speed, in which a short channel phenomenon does not occur during the manufacture, by forming source regions, where impurity concentration is higher than that in drain regions. CONSTITUTION:Processes up to the first impurity implanting process for forming a source region 6c are the same as the conventional processes. Impurity D1, e.g., B, is simultaneously implanted in source regions and a drain region 7a. As the second impurity implanting process, a resist film 12 is formed so that a window 13 is provided only at a part of a source forming region other than a part of the channel side. Impurity D2, which imparts the same conducting type as that of the impurity D1, e.g., B, is implanted. In the source region 6d, e.g., As is used as the impurity D1 and P is used as the D2. The source resistance values of the source regions 6c and 6d can be reduced, and the switching speed becomes quick. The impurities are not implanted in the channel side part of the source regions in the second impurity implanting process. Therefore the short channel phenomenon does not occur when the impurities are activated. |
