摘要 |
A trench MOSFET comprising source regions having a doping profile of a Gaussian-distribution along the top surface of epitaxial layer and floating dummy cells formed between edge trench and active area is disclosed. A SBR of n region existing at cell corners renders the parasitic bipolar transistor difficult to turn on, and the floating dummy cells having no parasitic bipolar transistor act as buffer cells to absorb avalanche energy when gate bias is increasing for turning on channel, therefore, the UIS failure issue is avoided and the avalanche capability of the trench MOSFET is enhanced. |