| 摘要 |
PURPOSE:To enable the omission of the patterning step for forming a contact part of a cell plate electrode by connecting the cell plate electrode and a semiconductor substrate electrically in a predetermined region at the bottom of a groove. CONSTITUTION:After removing a silicon thin film 13, a silicon oxide film 2 is formed on a surface of the silicon thin film 13 and the remaining part forms a groove 121. Next, P-type impurity such as boron is doped to deposit a silicon thin film 30 with an increased conductivity. At this time, the groove of a cell part is filled with the silicon thin film 30, but the groove in a predetermined region is prevented from being filled. The silicon thin film 30 is etched to leave the silicon thin film 30 inside the groove 121 in the cell part and also to leave the silicon thin film 30 only on the side walls of the groove 121 in a predetermined region. The remaining part forms the groove 122. Next, the silicon oxide film 4 exposed at the bottom of the groove 122 in a predetermined region is removed with a buffer hydrofluoric acid solution to expose a surface of the silicon substrate 1 in a region 14' at the bottom of the groove 122. Then, a silicon thin film 31 including P-type impurity such as boron is deposited, and is etched to fill the groove 122 completely. |
