摘要 |
A trench isolation structure for high voltage device is provided including a high voltage well, a low voltage well, and trench oxide. The high voltage well is formed first to be the deep junction isolation of isolation region. Next, the trench oxide isolation is formed overlying the high voltage well. Then, the low voltage well with higher concentration is formed underlying the trench oxide by using high energy implant. The isolation structure is a trench oxide(dielectric isolation)-junction isolation structure.
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