Gate electrode in a trench for power MOS transistors

摘要

A trench-typed power MOS transistor comprises a trench-typed gate area, which includes a gate conductor and an isolation layer. A thin sidewall region of the isolation layer is formed between the gate conductor and a well region. A thick sidewall region of the isolation layer is formed between the gate conductor and a double diffusion region. A thick bottom region of the isolation layer is formed between the gate conductor and a deep well region.