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为了解决薄外延横向功率器件的纵向耐压问题,提出了一种带有N型浮空岛的新型LDMOS.与传统LDMOS不同,该结构在漏端下方的衬底耗尽层内加入多个纵向排列的N型浮空岛,扩展了衬底的耗尽层,降低了漏端下方的高电场,在纵向引入新的峰值电场,优化了器件的横向和纵向电场分布,大幅提高了器件的击穿电压.利用Sentaurus TCAD软件对新结构进行了仿真.结果表明,漂移区长度均为80 μm时,新结构的击穿电压为964V,比相同漂移区长度下的传统LDMOS提高了113.7％,优值为1.01MW·cm-2,比传统LDMOS提高了211％.“,”A novel LDMOS with N-type doped floating islands was proposed to solve the premature breakdown phenomenon in the vertical direction of lateral power devices with a thin epitaxial layer.The difference between this structure and the conventional LDMOS was that the multiple N-type doped floating islands were serially placed to the substrate depletion layer vertically below the drain region.These N-type floating islands expanded the depletion region boundary in the substrate layer,which had lowered the high electric field underneath drain area,and imported several new peak values in vertical direction,which had optimized the lateral and vertical electric field distribution and had improved the breakdown voltage significantly.The electrical characteristics of the proposed structure were simulated by the Sentaurus TCAD tools.The numerical results demonstrated that within the same drift region length of 80 μm,the breakdown voltage of the novel structure was 964 V,which was increased by 113.7％ compared with that of the conventional LDMOS.Also,the simulated figure of merit was 1.01 MW· cm-2,which was improved by 211％.