Key Laboratory of Electronics Engineering, College of Heilongjiang Province, Major Laboratories of Integrated Circuits, Heilongjiang University, Harbin 150080, China.
Sensors (Basel). 2012;12(5):6369-79. doi: 10.3390/s120506369. Epub 2012 May 14.
A novel nc-Si/c-Si heterojunction MOSFETs pressure sensor is proposed in this paper, with four p-MOSFETs with nc-Si/c-Si heterojunction as source and drain. The four p-MOSFETs are designed and fabricated on a square silicon membrane by CMOS process and MEMS technology where channel resistances of the four nc-Si/c-Si heterojunction MOSFETs form a Wheatstone bridge. When the additional pressure is P, the nc-Si/c-Si heterojunction MOSFETs pressure sensor can measure this additional pressure P. The experimental results show that when the supply voltage is 3 V, length-width (L:W) ratio is 2:1, and the silicon membrane thickness is 75 μm, the full scale output voltage of the pressure sensor is 15.50 mV at room temperature, and pressure sensitivity is 0.097 mV/kPa. When the supply voltage and L:W ratio are the same as the above, and the silicon membrane thickness is 45 μm, the full scale output voltage is 43.05 mV, and pressure sensitivity is 2.153 mV/kPa. Therefore, the sensor has higher sensitivity and good temperature characteristics compared to the traditional piezoresistive pressure sensor.
本文提出了一种新型的 nc-Si/c-Si 异质结 MOSFET 压力传感器，其源极和漏极采用了四个 nc-Si/c-Si 异质结 p-MOSFET。这四个 p-MOSFET 通过 CMOS 工艺和 MEMS 技术设计和制造在一个正方形硅膜上，其中四个 nc-Si/c-Si 异质结 MOSFET 的沟道电阻形成了一个惠斯通电桥。当有外加压力 P 时，nc-Si/c-Si 异质结 MOSFET 压力传感器可以测量这个外加压力 P。实验结果表明，当供电电压为 3 V、长宽比为 2:1、硅膜厚度为 75 μm 时，室温下压力传感器的满量程输出电压为 15.50 mV，压力灵敏度为 0.097 mV/kPa。当供电电压和长宽比与上述相同，硅膜厚度为 45 μm 时，满量程输出电压为 43.05 mV，压力灵敏度为 2.153 mV/kPa。因此，与传统的压阻式压力传感器相比，该传感器具有更高的灵敏度和良好的温度特性。
