In this work, GaN/AlN/AlGaN MOS-HEMT with a cavity below the gate towards the drain side is studied for its sensitivity analysis and viability as a biosensor. The analysis is done by dielectric modulation of the cavity region to emulate the presence of different dielectric biomolecules and charged biomolecules by interface charge variation. MOSFET-based dielectrically modulated sensors have been a success experimentally and this work extends and demonstrates this concept with GaN HEMT. The device performance is evaluated through the shift in threshold voltage (V_th) and drain current (I_DS), which are used as performance metrics. The proposed device structure simulations were performed with ATLAS Silvaco device simulation tool which depicts the bio-immobilization in the cavity leads to the changes in electrostatic properties like conduction band offset, two-dimensional electron gas (2DEG) sheet carrier concentration and channel potential. The simulation analysis reveals V_th and I_DS shift up to 1.1 V and 153.7 mA/mm for the neutral biomolecules, whereas for deoxyribo nucleic acid, the shift is up to 0.30 mV and 65.2 mA/mm, respectively, implying a highly sensitive device. The AlGaN layer thickness and cavity fill height variations on device sensitivity are also reported.

在这项工作中，研究了 GaN/AlN/AlGaN MOS-HEMT，其在栅极下方朝向漏极侧有一个空腔，用于其灵敏度分析和作为生物传感器的可行性。该分析是通过空腔区域的介电调制来模拟不同介电生物分子和通过界面电荷变化的带电生物分子的存在。基于 MOSFET 的介电调制传感器在实验上取得了成功，这项工作通过 GaN HEMT 扩展并展示了这一概念。_器件性能通过阈值电压 ( Vth ) 和漏极电流₍ IDS)，用作性能指标。所提出的器件结构模拟是使用 ATLAS Silvaco 器件模拟工具进行的，该工具描述了空腔中的生物固定导致静电特性的变化，如导带偏移、二维电子气 (2DEG) 片载流子浓度和通道电位。模拟分析表明，对于中性生物分子， V _th和I _DS偏移高达 1.1 V 和 153.7 mA/mm，而对于脱氧核糖核酸，偏移分别高达 0.30 mV 和 65.2 mA/mm，这意味着该设备具有高灵敏度. 还报告了 AlGaN 层厚度和空腔填充高度对器件灵敏度的影响。