| 摘要 |
<p>PURPOSE: A manufacturing method of a semiconductor device is provided to uniformly control the entire buffer oxide film thickness of a trench MOSFET device by forming an additional buffer oxide film in the upper part of a buffer oxide layer. CONSTITUTION: A first buffer oxide layer(306a) is formed in the upper part of a semiconductor substrate(300) where a gate oxidation layer(302) for a trench gate electrode and a polysilicon layer(304) are formed. A protection nitride layer is formed on the top of the semiconductor substrate in which the first buffer oxide layer is formed. The patterned protection nitride layer is removed after patterning the first buffer oxide layer and the protection nitride layer. A second buffer oxide layer(314) is formed on the top of the patterned first buffer oxide layer.</p> |
