| 摘要 |
PURPOSE:To reduce the capacity of a vertical signal line by a method wherein a well region just under a source or drain region connected to a vertical signal line is made lower in terms of impurity concentration than other parts, when a well region provided semiconductor substrate is divided into a multiplicity of regions by means of element dividing oxide films and the resultant individual well regions are provided with solid state image pickup element, respectively. CONSTITUTION:A P type well region 12 is diffusedly formed on an N type Si substrate 11 and then is divided into a multiplicity of elements by means of a mltiplicity of thick element isolating oxide films 17. Each of the regions 12 is provided with an N<+> type source region 13 and a drain region 14 that are diffusedly formed, and well regions 12 exposed therebetween the provided with gate insulating films 15 whereon gate electrodes 16 are installed. After this, the entire surface is covered with an interlayer insulating film 18 which is turn is provided with an opening whereinto a vertical signal line 19 is attached for the formation of a picture element. In this construction, the well region 12 under the region 14 whereupon the signal line 19 is installed is to be N<-> type region 12' particularly with low impurity concentration. Thus the capacity of the signal line 19 is reduced thereby reducng random noises. |
