Delta doped and counter doped dynamic threshold voltage MOSFET for ultra-low voltage operation

摘要

A dynamic threshold voltage IGFET such as a MOSFET is operable at voltages of 0.6 volt or less. The threshold voltage of the transistor is reduced to zero volt or less by interconnecting the gate contact and the device body in which the voltage controlled channel is located. The channel region is delta-doped or counter-doped which permits superior performance for high-end VSLI applications. A selective epitaxy on a counter-doped substrate can be used in a counter-doped device. Doped wells can be used in a bulk silicon substrate in forming the devices. Trenching can be used to isolate devices in the doped wells.