Structure to improve MOS transistor on-breakdown voltage and method of making the same

摘要

A novel MOS transistor structure and methods of making the same are provided. The structure includes a MOS transistor formed on a semiconductor substrate of a first conductivity type with a plug region of first conductivity type formed in the drain extension region of second conductivity type (in the case of a high voltage MOS transistor) or in the lightly doped drain (LDD) region of second conductivity type (in the case of a low voltage MOS transistor). Such structure leads to higher on-breakdown voltage. The inventive principle applies to MOS transistors formed on bulky semiconductor substrate and MOS transistors formed in silicon-on-insulator configuration.