Side Trench Field Plate Of SOI Lateral Power Devices

The Silicon On Insulator?SOI?is widely used in high performance power devices due to its advantages of high speed,high integration,low power consumption,strong radiation resistance and easy isolation.SOI LDMOS is one important device of the power devices.The research of LDMOS is mainly fouces on the trade-off between the specific on-resistance(R_on,sp)and the breakdown voltage?BV?,which is how to increase the BV and reduce the R_on,sp.New materials,new processes,new structures and new technologies are proposed to solve the trade-off between the R_on,sp and the BV.To solve the same issue in SOI LDMOS,a new technology named side trench field plate technology is proposed in this thesis,and two kinds of SOI LDMOS using this technology are studied and analyzed.The sied trench field plate can reduce the electric field peak at PN junction and introduce a new peak electric field at the boundary of field plate.The sied trench field plate makes the electric field distribution in the drift region tend to be uniform,modulates the surface electric field distribution to improve the BV.This thesis focuses on the study of SOI LDMOS with side trench field plate,the main work includes:?1?New structures of SOI LDMOS with side trench field plate in oxide or high-k dielectric trench are proposed.The new structures introduces the oxide or high-k dielectric trench in the drift region,and the side gate field plate and the side drain field plate are introduced into the dielectric trench.The three-dimensional simulation software DAVINCI is used to simulate the new SOI LDMOS.The Influences of doping concentration in drift region,side gate field plate length,side drain field plate length and dielectric constant on the BV and R_on,sp of the new SOI LDMOS are analyzed on qualitatively.Compared with the traditional SOI LDMOS,the BV of SOI LDMOS with side trench field plate in oxide dielectric increases 26.6%while keeping the specific on resistance unchanged.Compared with the SOI LDMOS with side trench field plate in oxide dielectric,the BV and R_on,sp of SOI LDMOS with side trench field plate in hing-k dielectric are increases 18.8%and reduces 11.7%respectivity.?2?The process scheme of SOI LDMOS with side trench field plate is designed,and the process of SOI LDMOS with side trench field plate is simulated by the sentuaurs TCAD software.Which made some guidance for the further fabrication of the SOI LDMOS with side trench field plate.