A dielectric-modulated field-effect transistor for biosensing
A dielectric-modulated field-effect transistor for biosensing
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DOI：
10.1038/nnano.2007.180
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发表时间：
2007-07-01
影响因子：
38.3
通讯作者：
Choi, Yang-Kyu
中科院分区：
文献类型：
--
作者：
Im, Hyungsoon;Huang, Xing-Jiu;Choi, Yang-Kyu
基于场效应晶体管(FET)的生物传感器的兴趣来自于将生物检测能力整合到现有半导体技术中的前景(1)。在场效应晶体管(FET)的基础上，一个电动栅极控制着通过半导体通道的电荷流动。在许多已提出的FET生物传感器中，表面与溶液中生物分子的相互作用会影响栅极或沟道的运行(2-19)。然而，这些设备的灵敏度往往有限。我们在这里表明，具有垂直间隙的FET生物传感器对链霉亲和素与生物素的特定结合很敏感。链霉亲和素的结合改变了栅极的介电常数(和电容)，导致操作FET的阈值电压发生了很大的漂移。垂直带隙是用简单的薄膜沉积和湿法刻蚀技术制造的。这可能是平面纳米间隙FET的优势，后者需要光刻处理(20-24)。我们相信，介电调制FET(DMFET)为生物分子检测提供了一种有用的方法，可以扩展到许多其他系统。
Interest in biosensors based on field-effect transistors (FETs), where an electrically operated gate controls the flow of charge through a semiconducting channel, is driven by the prospect of integrating biodetection capabilities into existing semiconductor technology(1). In a number of proposed FET biosensors, surface interactions with biomolecules in solution affect the operation of the gate or the channel(2-19). However, these devices often have limited sensitivity. We show here that a FET biosensor with a vertical gap is sensitive to the specific binding of streptavidin to biotin. The binding of the streptavidin changes the dielectric constant (and capacitance) of the gate, resulting in a large shift in the threshold voltage for operating the FET. The vertical gap is fabricated using simple thin-film deposition and wet-etching techniques. This may be an advantage over planar nanogap FETs, which require lithographic processing(20-24). We believe that the dielectric-modulated FET (DMFET) provides a useful approach towards biomolecular detection that could be extended to a number of other systems.