A new lateral power MOSFET structure, named the Accumulation LDMOST (ALDMOST), is proposed. It relies on creation of an accumulation layer along the surface of the drift region. This surface accumulation layer exists only in the ON state. Simulation studies indicate that the product of the ON resistance by the area (

) of the ALDMOST is one-third to one-fifth that of a conventional LDMOST rated at the same breakdown voltage.