| 摘要 |
PURPOSE:To reduce the displacement of a mask coated on the source and drain diffused layers of a semiconductor device and reduce the depth of its junction by forming the source and drain diffused layers at both n-channel and p-channel sides with one mask and coating the layers with Si3N4 film. CONSTITUTION:A deep p-type layer 2 is formed on an n-type silicon substrate 1, and coated with an SiO2 film 3. The film 3 is coated with an Si3N4 film 4, which is then etched with a resist mask 5. Then, the mask 5 is removed to form an SiO2 film 6 of predetermined thickness and to set the threshold value of a parasitic MOS element at desired value. After it is then coated with a resist 7 and the films 4, 3 are selectively removed, the mask is removed to form n-type source 8 and drain 9. Then, the layers 4, 3 are similarly etched at the p-channel side 16, and p-type source 10 and drain 11 are formed without mask. Then, a resist mask 13 is coated thereon, the SiO2 film 6 is etched on the gate region to newly form a gate oxide film 14 thereon to thus form a gate electrode 15. This process can simultaneously from both the source and the drain of the channels 16, 17 with the same one mask to prevent the displacement of the mask and to eliminate the increase of the depth of the junction between the source and the drain layers at a value more than required. |
