具有L型栅极场板的双槽双栅绝缘体上硅器件新结构

为了降低绝缘体上硅（SOI）功率器件的比导通电阻，同时提高击穿电压，利用场板（FP）技术，提出了一种具有L型栅极场板的双槽双栅SOI器件新结构.在双槽结构的基础上，在氧化槽中形成第二栅极，并延伸形成L型栅极场板.漂移区引入的氧化槽折叠了漂移区长度，提高了击穿电压；对称的双栅结构形成双导电沟道，加宽了电流纵向传输面积，使比导通电阻显著降低；L型场板对漂移区电场进行重塑，使漂移区浓度大幅度增加，比导通电阻进一步降低.仿真结果表明：在保证最高优值条件下，相比传统SOI结构，器件尺寸相同时，新结构的击穿电压提高了123%，比导通电阻降低了32%；击穿电压相同时，新结构的比导通电阻降低了87.5%；相比双槽SOI结构，器件尺寸相同时，新结构不仅保持了双槽结构的高压特性，而且比导通电阻降低了46%.

A Dual-Trench-Gate Silicon on Insulator Device with a L-shaped Gate Field Plate

To reduce the on-resistance and enhance the breakdown voltage of silicon on insulator (SOI),a Dual-Trench-Gate silicon on insulator device with a L-shaped gate field plate is proposed by using the field plate (FP) technology.On the basis of the dual-trench structure,a second gate is formed in the oxidation trench,and the L-shaped gate field plate is formed in the extension of the second gate.The drift region length is folded,the breakdown voltage is increased.The dual gates form dual conduction channels,which widen the vertical conduction area and reduced the specific on-resistance.The L-shaped gate field plate modulates the electric field in the drift region,increases the optimized doping concentration of the drift region significantly and further reduces the specific on-resistance.The simulator results show that under the condition of the highest FOM,as compared with a conventional SOI device at the same cell pitch,the breakdown voltage is increased by 123%,and the specific on-resistance is reduced by 32%.The specific on-resistance is reduced by 87.5% at the same breakdown voltage.Compared with a dual-trench SOI device with the same cell pitch,the proposed device not only maintains the high breakdown voltage as the dual-trench SOI device,but also reduces the specific on-resistance by 46%.