【摘要】 提出了一种可变低k(相对介电常数)介质层(variablelowkdielectriclayer,VLkD)SOI高压器件新结构,该结构的埋层由可变k的不同介质组成.基于电位移连续性原理,利用低k提高埋层纵向电场和器件纵向耐压,并在此基础上提出SOI的介质场增强原理.基于不同k的埋层对表面电场的调制作用,使器件横向耐压提高,并给出VLkDSOI的RESURF判据.借助2D器件仿真研究了击穿特性与VLkDSOI器件结构参数之间的关系.结果表明,对kIL=2,kIH=3·9,漂移区厚2μm,埋层厚1μm的VLkD器件,埋层电场和器件耐压分别达248V/μm和295V,比相同厚度的常规SOI器件的埋层电场和耐压分别提高了93%和64%.更多还原

【Abstract】 A novel SOI high voltage device structure with a variable low k dielectric layer (VLkD) is proposed.The buried layer is made up of dielectrics with variable k.The vertical electric field of the buried layer and the vertical breakdown voltage are enhanced due to the low dielectric constant.An enhanced dielectric electric field principle is then proposed.The modulation effect of the buried dielectric layer with different k on the surface electric field increases the lateral breakdown voltage.The RESURF criterion for VLkD SOI is developed.The dependence of breakdown characteristics on the structure parameters of VLkD is researched by 2D device simulator.It is shown that an electric field of the buried layer of 248V/μm and breakdown voltage of 295V can be obtained for a VLkD structure with a 2μm thick Si layer and 1μm composite buried layer with k_ IL=2 and k_ IH=3.9.The electric field of the buried layer and breakdown voltage are enhanced by 93% and 64%,respectively, compared to conventional SOI with a 1μm buried oxide layer.更多还原