| 摘要 |
PURPOSE:To readily form an insulating layer by forming a mask layer on a substrate, and then forming in a self-aligning manner an element separating insulating layer. CONSTITUTION:A mask layer 3 is formed on a substrate 1. The layer 3 has a silicon oxide layer 21, silicon nitride layers 22, 24, and a silicon oxide layer 23 added with phosphorus. Then, a mask layer 25 made of silicon nitride is formed. Subsequently, an interelement separating insulating layer 25 made of silicon oxide layer is formed. Thereafter, the layers 25, 24 are removed, and a P type impurity implanting region 27 is formed. An element separating groove 28 is formed by etching with the layers 3, 26 as masks. Then, the layer 23 is removed, and a silicon oxide layer 29 is formed. Thereafter, a silicon oxide layer 30 is formed in the groove 28. |
