Abstract: 0.5μm-gate-length lateral double-diffused metal-oxide-semiconductor field-effect transistors (LDMOSFETs) with low barrier body contact (LBBC) and body tied to the source (BTS) were fabricated on silicon-on-insulator (SOI) substrates.The back-gate effects on front-channel subthreshold characteristics,on-resistance,and off-state breakdown characteristics of these devices are studied in detail.The LDMOSFETs with the LBBC structure show less back-gate effect than those with the BTS structure due to better control of the floating body effect and suppression of the parasitic back-channel leakage current.A model for the SOI LDMOSFETs has been given,including the front- and back-channel conductions as well as the bias-dependent series resistance.

Key words: SOI, LDMOSFET, back-gate effect