Analysis and Fabrication of an LDMOS With High-Permittivity Dielectric

A lateral double-diffusion MOSFET with a uniform high-permittivity (HK) dielectric field plate (FP) is manufactured and presented in this letter. The HK dielectric FP is capable of cutting both electric peak fields at the channel p-n junction and the edge of FP, providing higher breakdown voltage (BV) based on a novel mechanism. The Pb(Zr_0.53, Ti_0.47)O₃ (PZT) is taken as the HK dielectric material for its large preanneal permittivity. The test results indicate that, based on two identical devices except for the dielectric material, the BV of the one with PZT FP is more than three times of that of the counterpart with a SiO₂ dielectric, approximately 350 and 100 V, respectively.