| 摘要 |
PROBLEM TO BE SOLVED: To reduce the aspect ratio of a contact hole by patterning a first and a second conductive film so that they may be left over on a diffusion layer on a semi conductor substrate. SOLUTION: A LOCOS oxide film 102, a gate oxide film 103, and a polycrystalline silicon film 104 are formed in this order on a semiconductor substrate 101. After that, a silicon dioxide film 105 is formed by a CVD method. Nextly, phosphor ions are implanted through the gate oxide film 103 to form a low-density impurity diffusion layer 106. Then, arsenide ions are implanted to form a high-density impurity diffusion layer 108. On these impurity layers 106, 108, a first and a second buried conductive layer 109, 113 are formed. After that, photo resist 114 is applied and is processed to the pattern of each of the buried conductive layers 109, 113. By this method, the aspect ratio of a contact hole 120 can be reduced. |
