LDMOS WITH ADAPTIVELY BIASED GATE-SHIELD

摘要

An LDFET is disclosed. A source region is electrically coupled to a source contact. A lightly doped drain (LDD) region has a lower dopant concentration than the source region, and is separated from the source region by a channel. A highly doped drain region forms an electrically conductive path between a drain contact and the LDD region. A gate electrode is located above the channel and separated from the channel by a gate dielectric. A shield plate is located above the gate electrode and the LDD region, and is separated from the LDD region, the gate electrode, and the source contact by a dielectric layer. A control circuit applies a variable voltage to the shield plate that: (1) accumulates a top layer of the LDD region before the transistor is switched on; and (2) depletes the top layer of the LDD region before the transistor is switched off.