A New Method of Increasing Breakdown Voltage and Decreasing Self Heating in SOILDMOS with Two Buried Oxide Layer

In this paper we compare the LDMOS transistors onboth bulk silicon and SOI layer. We will show that the cut-offfrequency in SOI LDMOS compared to simple LDMOS is increasedby about 36.36 percent while leakage current is decreased by about161.11 percent. In this paper we discuss the effect of buried oxidedistance from Si/SiO2 interface in order to obtain higher breakdownvoltage, higher cut-off frequency and lower self heating effect. Forour investigated SOI-LDMOS with two buried oxide layer,breakdown voltage is 115 V while for the SOI-LDMOS with oneburied oxide layer is 95 V; so breakdown voltage is increased by21.05 percent in SOI-LDMOS with two buried oxide layer.Furthermore the maximum temperature in the hot spot for SOILDMOSis 386 K while it is 300 K for SOI-LDMOS with two buriedoxide layer. Therefore self heating is decreased by 28.36 percent inSOI-LDMOS with two buried oxide layer.

Keywords:

SOI-LDMOS transistor , SOI-LDMOS transistorwith two buried oxide , Breakdown voltage , Self heating