Injected charges in partial SOI LDMOSFETs: A new technique for improving the breakdown voltage

High breakdown voltage and reduced on-resistance are desired characteristics in power MOSFETs. In order to obtain an excellent performance of lateral double-diffused MOSFET (LDMOS) devices, we have proposed a new technique in which at the surface of buried oxide, negative and positive charges are incorporated, periodically. This strategy modulates the electric field and causes high breakdown voltage. Also, by considering the charges at interface of the buried oxide, depletion islands form in the drift region that the current density increases on the top of the drift region and the on-resistance decreases. Our simulation with two-dimensional ATLAS simulator shows that an Injected Charge in Buried Oxide of Partial SOI LDMOSFET (ICBO-PSOI) has considerable improvement in high frequency with reduced switching delay.

► A new LDMOS transistor on partial SOI is proposed in this paper (ICBO-PSOI).
► Negative and positive charges are considered on the BOX interface.
► Increased electric field in the BOX causes high breakdown voltage in ICBO-PSOI.
► Our simulation shows an excellent behavior of the ICBO-PSOI in power applications.