BioFETs have potential applications in detecting various kinds of pathogens due to their label free and highly stable detection of biological species with high responsivity and reliability. This paper investigates detection of different types of high-k biomolecules using Ge-source L-tunnel field effect transistor in the presence of watery medium. The entire detection scheme relies on the tunneling effect at Ge-source and Si-channel junction for introducing various types of biomolecules through the vertical arm of ‘L’ which is used as the cavity, the main sensing area of the device. The device characteristics are affected by the dielectric constant of the biomolecules. TCAD tools are used to obtain the results. In addition, the impact of doping concentration of the source, drain and substrate on sensitivity is investigated. Furthermore, effects of the variation of source height and temperature on sensitivity of the sensor are studied. We achieve 48.46% improvement in sensitivity using the aforesaid device which is pretty high compared to Si based structure. Our findings suggest that use of Ge-source in LTFET yields far better sensitivity than Si based and many other devices reported earlier.

BioFETs 在检测各种病原体方面具有潜在的应用，因为它们具有高响应性和可靠性的无标记和高度稳定的生物物种检测。本文研究了在水介质存在下使用 Ge 源 L 型隧道场效应晶体管检测不同类型的高 k 生物分子。整个检测方案依赖于Ge源和Si沟道结处的隧道效应，通过“L”的垂直臂引入各种类型的生物分子，该垂直臂用作腔体，该器件的主要传感区域。器件特性受生物分子介电常数的影响。TCAD 工具用于获得结果。此外，还研究了源极、漏极和衬底的掺杂浓度对灵敏度的影响。此外，研究了源高度和温度变化对传感器灵敏度的影响。使用上述器件，我们实现了 48.46% 的灵敏度提高，与 Si 基结构相比相当高。我们的研究结果表明，在 LTFET 中使用 Ge 源产生的灵敏度远高于 Si 基器件和之前报道的许多其他器件。