摘要 |
An isolation structure of a semiconductor device including a channel stop diffusion region selectively formed on a portion of a single crystalline silicon substrate disposed beneath an edge of a field oxide film formed on the substrate, thereby capable of selectively increasing, irrespective of a pattern size of the field region, a channel ion concentration at an edge of a field region where the field region is connected to an active region and which region is a weak area serving to decrease a channel stop ion concentration at an interface between the field oxide film and the silicon substrate and to decrease a threshold voltage of a field transistor due to a small thickness thereof and thereby locally increasing the threshold voltage. By the local increase in threshold voltage, it is possible to prevent a degradation in insulating characteristic of the field transistor with a small pattern size.
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