Kang Heung Seok, Lee Kang-Hee, Yang Dong-Youk, You Byoung Hee, Song In-Hyouk
1Korea Atomic Energy Research Institute, 150 Deokjin-dong, Yuseong-gu, Daejeon, Republic of Korea.
LOGTECH Co. Ltd., 914 Gumgang Hightech Valley 1st, Sungnam-si, Gyeonggi-do Republic of Korea.
Nanomicro Lett. 2015;7(3):282-290. doi: 10.1007/s40820-015-0041-9. Epub 2015 May 6.
A vertically movable gate field effect transistor (VMGFET) is proposed and demonstrated for a micro-accelerometer application. The VMGFET using air gap as an insulator layer allows the gate to move on the substrate vertically by external forces. Finite element analysis is used to simulate mechanical behaviors of the designed structure. For the simulation, the ground acceleration spectrum of the 1952 Kern County Earthquake is employed to investigate the structural integrity of the sensor in vibration. Based on the simulation, a prototype VMGFET accelerometer is fabricated from silicon on insulator wafer. According to current-voltage characteristics of the prototype VMGFET, the threshold voltage is measured to be 2.32 V, which determines the effective charge density and the mutual transconductance of 1.545×10 C cm and 6.59 mA V, respectively. The device sensitivity is 9.36-9.42 mV g in the low frequency, and the first natural frequency is found to be 1230 Hz. The profile smoothness of the sensed signal is in 3 dB range up to 1 kHz.
本文提出并演示了一种用于微加速度计应用的垂直可移动栅极场效应晶体管（VMGFET）。该VMGFET采用气隙作为绝缘层，使得栅极能够在外力作用下在衬底上垂直移动。利用有限元分析来模拟所设计结构的力学行为。在模拟过程中，采用1952年克恩县地震的地面加速度谱来研究传感器在振动中的结构完整性。基于该模拟，在绝缘体上硅晶圆上制造了一个VMGFET加速度计原型。根据该原型VMGFET的电流 - 电压特性，测得阈值电压为2.32 V，这分别决定了有效电荷密度和跨导为1.545×10 C/cm和6.59 mA/V。该器件在低频时的灵敏度为9.36 - 9.42 mV/g，并且发现其第一固有频率为1230 Hz。传感信号的轮廓平滑度在高达1 kHz的频率范围内处于3 dB范围内。
