| 摘要 |
<p>A method for fabricating a semiconductor device is provided to improve reliability of a device and to prevent a well breakdown voltage by forming an oxide layer for a voltage on a semiconductor substrate. An oxide layer having a thickness of 100 to 200 angstrom corresponding to a high voltage region of a well is formed on a semiconductor substrate(200). A first photoresist pattern is formed on the oxide layer. Thereafter, the oxide layer is selectively etched by using the first photoresist pattern as a mask to have a thickness of 300 to 400 angstrom corresponding to a low voltage region of the well. The first photoresist pattern is removed and a poly silicon layer(206a) is coated on the etched oxide layer. A second photoresist pattern is formed on the poly silicon layer. A poly silicon layer pattern is formed by selectively etching the poly silicon layer until the etched oxide layer is exposed through an etching process using the second photoresist pattern as a mask. The second photoresist pattern is removed and a drift region is formed in the semiconductor substrate by performing an ion implantation using an oxide layer pattern with a thickness corresponding to the poly silicon layer pattern and a high voltage, as a mask.</p> |
