| 摘要 |
PURPOSE: A method for manufacturing a high voltage device having a polysilicon region of a trench structure is provided to improve a maximum operation voltage by simultaneously reducing the resistance of a source portion and a channel portion, and to decrease manufacturing cost by omitting a diffusion process. CONSTITUTION: An N-type drift region(22) and a P-type drift region(21) are formed on a substrate(20). A trench is formed in either one of the two drift regions. The trench is filled with polysilicon(26). A high density diffusion layer is formed on the polysilicon and the drift region where the trench is not formed. An oxide layer is formed on the gap between the N-type and P-type drift regions. A gate electrode is formed on the oxide layer. A metal electrode is formed on the high density diffusion layer. |
