A new SOI high voltage device based on E-SIMOX substrate

A new NI (n+ charge islands) high voltage device structure based on E-SIMOX (epitaxy-the separation by implantation of oxygen) substrate is proposed. It is characterized by equidistant high concentration n+-regions on the top interface of the dielectric buried layer. Inversion holes caused by the vertical electric field (Ev) are located in the spacing of two neighboring n+-regions on the interface by the force from lateral electric field (EL) and the compositive operation of Coulomb's forces with the ionized donors in the undepleted n+-regions. This effectively enhances the electric field of dielectric buried layer (EI) and increases breakdown voltage (Vb). An analytical model of the vertical interface electric field for the NI SOI is presented, and the analytical results are in good agreement with the 2D simulative results. EI = 568 V/μm and VB = 230 V of NI SOI are obtained by 2D simulation on a 0.375-μm-thick dielectric layer and 2-μm-thick top silicon layer. The device can be manufactured by using the standard CMOS process with addition of a mask for implanting arsenic to form NI. 2-μm silicon layer can be achieved by using epitaxy SIMOX technology (E-SIMOX).     

一种新的基于E-SIMOX衬底的PSOI高压器件

首次提出了一种新的采用E-SIMOX技术的界面电荷岛结构的PSOI高压器件(NI PSOI)。该结构在SOI器件介质层上界面注入形成一系列等距的高浓度N+区。器件外加高压时,纵向电场所形成的反型电荷将被未耗尽N+区内高浓度的电离施主束缚在介质层上界面,同时在下界面积累感应电子。详细研究NI PSOI工作机理及相关结构参数对BV的影响,在0.375μm介质层、2μm顶层硅上仿真获得188 V高耐压,较常规结构提高54.1%,其中附加场EI和ES分别达到190 V/μm和13.7 V/μm。     

一种新的基于E-SIMOX衬底的SOI高压器件

本文提出一种新的基于E-SIMOX衬底的n+电荷岛结构的SOI高压器件（NI SOI）。该结构在SOI器件介质层上界面注入形成一系列等距的高浓度n+区。纵向电场（EV）所形成的反型电荷将被来自横向电场（EL）的电场力和未耗尽n+区内高浓度电离施主杂质的库仑力综合作用下固定于界面两个n+之间,从而能有效的提高介质场（EI）,增强器件的击穿电压（VB）。提出的NI SOI的纵向解析模型与二维仿真结果相吻合。对0.375μm的介质层,2μm顶层硅的NI SOI 器件,EI =568V/μm和VB =230V。该器件在工艺上通过注入砷形成高浓度n+区,使用外延技术得到2μm的顶层硅(即E-SIMOX技术),它除了增加一张掩模版以外,和常规的CMOS工艺完全兼容。