| 摘要 |
<p>A method of manufacturing a semiconductor device comprises the steps of: forming an oxide film on the surface of a semiconductor substrate, and thereafter injecting ions of a first conductivity type on the entire surface of the semiconductor substrate (1); forming a first well (6) through a first thermal diffusion; injecting ions of a second conductivity type through the oxide film into a second well (9) region within the first well; and removing the oxide film formed on the second well region, and thereafter forming a second well having a depth smaller than that of the first well. The semiconductor device manufactured by this method has a first well of a first conductivity type formed on the entire surface of a semiconductor substrate and having higher impurity concentration than that of said semiconductor substrate and a second well of a second conductivity type opposite to said first conductivity type formed within a desired region of said first well. The depth of said first well which is suitable for forming trend capacitors is greater than that of said second well.</p> |
