| 摘要 |
PURPOSE:To curtail the time necessitated to erase contents of memory of a non volatile semiconductor memory unit by a method wherein a region not to be piled up with a channel region and also with a control gate is formed at a part of a floating gate. CONSTITUTION:A region 3' not to be piled up with a channel region 2 and also with a control gate 4 is formed at a part of a floating gate 3. By this way, because the region 3' is not piled up with the control gate 4, ultraviolet rays irradiated from the upper part is absorbed directly in the region 3' being a part of the floating gate, and absorbing efficiency of ultraviolet rays is improved. Moreover, because the region 3' is not placed on the channel region 2, no influence is affected on operating characteristic of the transistor. |
