A Novel SOI-LDMOSFET With Superior Electrical Performances

In current study, a new silicon-on-insulator (SOI) lateral-double-diffused metal-oxide-semiconductor field-effect transistor (LDMOSFET) is offered. Altering charge distribution causes less electric field crowding and enhanced breakdown voltage (VBR). For amending charge distribution, a metal region (COLUMN) and an air layer in the transistor are used. On the other the floating-body influence and impact ionization produce additional holes that are intensified via the parasitic bipolar junction transistor (BJT) in SOI-LDMOSFET that weaken the transistor efficiency. For that matter, a silicon layer under the BOX, attached to the channel area through the COLUMN has been replaced for reducing the hole density in the channel and control the BJT impact considerably. In order to attain the optimal outcomes, the COLUMN and the silicon layer under the BOX location and sizes are optimized carefully. DC and radio frequency features corresponding to the offered structure are examined through 2-D numerical simulation and compared with conventional SOI-LDMOSFET (C-SOI-LDMOSFET) features. The VBR corresponding to the offered structure develops by 229% comparing with that of the C-SOI-LDMOSFET structure. Though drain current of the suggested structure decreases slightly, 220% development in utmost output power density for the device is attained because of great enhancement of the VBR. Furthermore, the suggested structure causes the development of utmost oscillation frequency, utmost existing gain, and selfheating impacts corresponding to the device. Consequently, the suggested structure has excellent electrical performances comparing with the analogous device according to the conventional structure.

在本项研究中，提出了一种新型的硅绝缘体上硅（SOI）横向双扩散金属氧化物半导体场效应晶体管（LDMOSFET）。通过调整电荷分布，可以有效降低电场拥挤并提升击穿电压（VBR）。为了改善电荷分布，在晶体管中引入了金属区域（COLUMN）和空气层。然而，浮体效应和电离效应在SOI-LDMOSFET中产生额外的空穴，这些空穴通过寄生双极型晶体管（BJT）被放大，从而降低了晶体管的效率。针对这一问题，将位于BOX下方的硅层替换为通过COLUMN连接至沟道区域的硅层，以降低沟道中的空穴密度并显著控制BJT的影响。为了实现最佳性能，对COLUMN以及位于BOX下方的硅层的位置和尺寸进行了精心优化。通过二维数值模拟对所提出结构的直流和射频特性进行了研究，并将其与传统的SOI-LDMOSFET（C-SOI-LDMOSFET）的特性进行了比较。与C-SOI-LDMOSFET结构相比，所提出结构的VBR提升了229%。尽管建议结构的漏极电流略有下降，但由于VBR的大幅提升，设备的最大输出功率密度提高了220%。此外，所提出结构还导致设备最大振荡频率、最大存在增益和自加热效应的提高。因此，与传统的类似结构相比，所提出结构展现出卓越的电气性能。