| 摘要 |
PURPOSE:To obtain a device controlled accurately by positioning a source and drain region of a transistor by a first diffusion mask and further by diffusing an impurity having a great diffusion coefficient after diffusing an impurity having a small diffusion coefficient. CONSTITUTION:A P-type well 103 is formed on a N-type silicon substrate 10, thereafter, an oxidization film 102 is formed. Successively, an opening 105 and 104 are formed by utilizing a sheet mask and photoresist technique. Thereafter, an impurity having a small diffusion coefficient is diffused to the opening 105 and 104 to form a P-type diffusion layer 107 and 106. Successively, an oxidization film 108 is formed and is partially covered with a photoresist 109 to expose the P-type diffusion layer 107 to the atmosphere. Successively, the impurity having a high diffusion coefficient is diffused to form a N-type diffusion layer 110. Thereafter, an oxidization film 117 is formed, a part of the film 117 is removed by an etching and electrode 111 to 116 are formed. |
