| 摘要 |
PURPOSE:To implement a high speed in operation, by providing a semiconductor region at the lower part of a source or drain region and the junction part of a semiconductor substrate or a well region so that the junction part constitutes a low-impurity-concentration p-n junction part. CONSTITUTION:An MISFET having an LDD structure provided with a semiconductor region 8 is formed in a semiconductor integrated circuit device. A semiconductor region 12 is provided at the lower part of a source or drain region (semiconductor region 10) in said circuit device. Thus the extension of a depletion region at a p-n junction in a well region 2 can be made large. Therefore, junction capacity added to the MISFET can be reduced. A semiconductor region 11 having a reverse conducting type is formed in an MISFET having an LDD structure in the semiconductor integrated circuit device. In this device, the semiconductor region 12 is provided at the lower part of the source or drain region (semiconductor region 10). Therefore, the extension of the depletion region at the p-n junction with the semiconductor region 11 can be made large. Thus, the junction capacity added to the MISFET can be decreased. In this way, the speed of the semiconductor integrated circuit device is made high. |
