| 摘要 |
PURPOSE:To improve the integration of a semiconductor device by allowing the second conductive layer to remain only on the side part of a polysilicon layer when connecting a conductive layer such as a polysilicon layer for a MOS gate electrode to an impurity diffused layer, thereby reducing the size of the contacting region. CONSTITUTION:An SiO2 film 12, a polysilicon layer 14 and an SiO2 film 13 are superposed on an Si substrate 10, and simultaneously patterned. A polysilicon layer 15' is covered on the film 13 and the substrate 10, and the thickness is determined to the sum of the layer 14 and the film 12. In this case, the thickness H of the stepwise part becomes approx. twice of the thickness (h) of the flat part of the substrate 10. When reactive ion etching is performed to etch the thickness (h), a polysilicon layer 15 of 1/4 circular section remains in contact on the side surfce of the layer 14 and on the upper surfaces of the substrate 10. Eventually, when an N type layer is formed, N type impurity is diffused in the substrate from the layer 15 or through the layer 15, and an N type layer is also formed directly under the layer 15. According to this configuration, the conductive layer such as the layer 15 is formed in self-aligning manner, the size of the contacting area is shortened, thereby improving the integration. |
