| 摘要 |
PURPOSE:To eliminate contact holes and reduce the occupied area and realize high integrity by forming conductive side walls above source and drain regions. CONSTITUTION:Boron ions are implanted into regions beneath isolating oxide films 202 to form high concentration impurity regions 203. After 1st oxide film 204 and a nitride film 205 are successively deposited, a part of silicon of a substrate is exposed by photolighography and etching with an undersized mask of a selective oxidation mask. After 2nd oxide film is deposited, anisotropic etching is carried out to form side walls 206 and further channel doping is carried out to form a gate oxide film 207. After the oxide films 206 which remain as the side walls are removed, ions are implanted into the parts where the oxide films 206 are removed and source and drain impurity implanted regions 209 are obtained. An oxide film 210, 1st conductive film 212 and an oxide film 211 are successively deposited. After side walls are formed by anisotropic etching, a nitride film 213 is deposited. As the source and drain regions are connected to the wirings by the conductive side walls, contact holes can be eliminated.
|
