Creating high voltage FETs with low voltage process

摘要

An integrated circuit (IC) includes a high voltage first-conductivity type field effect transistor (HV-first-conductivity FET) and a high voltage second-type field effect transistor (HV-second-conductivity FET). The HV first-conductivity FET has a second-conductivity-well and a field oxide formed over the second-conductivity-well to define an active area. A first-conductivity-well is formed in at least a portion of the active area, wherein the first-conductivity-well is formed to have the capability to operate as a first-conductivity-drift portion of the HV-first-conductivity FET. The HV second-conductivity FET has a first-conductivity-well and a field oxide formed over the first-conductivity-well to define an active area. A channel stop region I s formed in at least a portion of the active area, wherein the channel stop region is formed to have the capability to operate as second-conductivity− drift portions of the HV-second-conductivity FET.