SEMICONDUCTOR POWER DEVICE HAVING WIDE TERMINATION TRENCH AND SELF-ALIGNED SOURCE REGIONS FOR MASK SAVING

摘要

A trench semiconductor power device with a termination area structure is disclosed. The termination area structure comprises a wide trench and a trenched field plate formed not only along trench sidewall but also on trench bottom of the wide trench by doing poly-silicon CMP so that the body ion implantation is blocked by the trenched field plate on the trench bottom to prevent the termination area underneath the wide trench from being implanted. Moreover, a contact mask is used to define both trenched contacts and source regions of the device for saving a source mask.