Sharma Bharat, Kim Jung-Sik
Department of Materials Science and Engineering, University of Seoul, Seoul, 02504, Korea.
Sci Rep. 2018 Apr 12;8(1):5902. doi: 10.1038/s41598-018-24324-z.
A low power, dual-gate field-effect transistor (FET) hydrogen gas sensor with graphene decorated Pd-Ag for hydrogen sensing applications was developed. The FET hydrogen sensor was integrated with a graphene-Pd-Ag-gate FET (GPA-FET) as hydrogen sensor coupled with Pt-gate FET as a reference sensor on a single sensor platform. The sensing gate electrode was modified with graphene by an e-spray technique followed by Pd-Ag DC/MF sputtering. Morphological and structural properties were studied by FESEM and Raman spectroscopy. FEM simulations were performed to confirm the uniform temperature control at the sensing gate electrode. The GPA-FET showed a high sensing response to hydrogen gas at the temperature of 25~254.5 °C. The as-proposed FET H sensor showed the fast response time and recovery time of 16 s, 14 s, respectively at the operating temperature of 245 °C. The variation in drain current was positively related with increased working temperature and hydrogen concentration. The proposed dual-gate FET gas sensor in this study has potential applications in various fields, such as electronic noses and automobiles, owing to its low-power consumption, easy integration, good thermal stability and enhanced hydrogen sensing properties.
开发了一种用于氢气传感应用的低功耗双栅场效应晶体管（FET）氢气传感器，其栅极采用石墨烯修饰的Pd-Ag。该FET氢气传感器在单个传感器平台上集成了作为氢气传感器的石墨烯-Pd-Ag栅极FET（GPA-FET）和作为参考传感器的Pt栅极FET。通过电子喷雾技术用石墨烯修饰传感栅电极，随后进行Pd-Ag直流/中频溅射。通过场发射扫描电子显微镜（FESEM）和拉曼光谱研究了其形态和结构特性。进行有限元模拟以确认传感栅电极处的温度均匀控制。GPA-FET在25~254.5 °C的温度下对氢气表现出高传感响应。所提出的FET氢气传感器在245 °C的工作温度下分别显示出16 s和14 s的快速响应时间和恢复时间。漏极电流的变化与工作温度和氢气浓度的增加呈正相关。本研究中提出的双栅FET气体传感器由于其低功耗、易于集成、良好的热稳定性和增强的氢气传感特性，在电子鼻和汽车等各个领域具有潜在应用。
