Analytical Model for the Electric Field Distribution of an SOI High Voltage Device with a Compound Dielectric Layer
复合介质层SOI高压器件电场分布解析模型

A novel SOI high voltage device with a compound dielectric buried layer is proposed,and an analytical model for its electric field and potential is established.A unified criterion of RESURF condition for CDL SOI and a uniform dielectric buried layer SOI device is given.The vertical electric field of the buried layer is enhanced due to the low k (permittivity) of the dielectric buried layer at the drain side,the electric field in the drift region is modulated by the compound dielectric layer with different k values,and both increase the breakdown voltage of the device.Based on the analytical model and the 2D device simulation,the electric field distribution and potential distribution are analyzed.The simulation results are in good agreement with the analytical results.It shows that the electric field of the buried layer and breakdown voltage of the CDL SOI when the low k value is 2 are enhanced by 82% and 58% compared to conventional SOI,respectively.