The monolithic integrated micro sensor is an important direction in the fields of integrated circuits and micro sensors. In this paper,a monolithic thermal vacuum sensor based on a micro-hotplate (MHP) and operating...The monolithic integrated micro sensor is an important direction in the fields of integrated circuits and micro sensors. In this paper,a monolithic thermal vacuum sensor based on a micro-hotplate (MHP) and operating under constant bias voltage conditions was designed. A new monolithic integrating mode was proposed,in which the dielectric and passiva- tion layers in standard CMOS processes were used as sensor structure layers,gate polysilicon as the sacrificial layer,and the second polysilicon layer as the sensor heating resistor. Then, the fabricating processes were designed and the monolithic thermal vacuum sensor was fabricated with a 0. 6μm mixed signal CMOS process followed by sacrificial layer etching technology. The measurement results show that the fabricated monolithic vacuum sensor can measure the pressure range of 2- 10^5 Pa and the output voltage is adjustable.展开更多
An on-chip microelectromechanical system was fabricated in a 0.5μm standard CMOS process for gas pressure detection. The sensor was based on a micro-hotplate (MHP) and had been integrated with a rail to rail operat...An on-chip microelectromechanical system was fabricated in a 0.5μm standard CMOS process for gas pressure detection. The sensor was based on a micro-hotplate (MHP) and had been integrated with a rail to rail operational amplifier and an 8-bit successive approximation register (SAR) A/D converter. A tungsten resistor was manufactured on the MHP as the sensing element, and the sacrificial layer of the sensor was made from polysilicon and etched by surface-micromachining technology. The operational amplifier was configured to make the sensor operate in constant current mode. A digital bit stream was provided as the system output. The measurement results demonstrate that the gas pressure sensitive range of the vacuum sensor extends from 1 to 105 Pa. In the gas pressure range from 1 to 100 Pa, the sensitivity of the sensor is 0.23 mV/Pa, the linearity is 4.95%, and the hysteresis is 8.69%. The operational amplifier can drive 200 Ω resistors distortionlessly, and the SAR A/D converter achieves a resolution of 7.4 bit with 100 kHz sample rate. The performance of the operational amplifier and the SAR A/D converter meets the requirements of the sensor system.展开更多
This paper describes a micro thermal shear stress sensor with a cavity underneath, based on vacuum anodic bonding and bulk micromachined technology. A Ti/Pt alloy strip, 2μm×100μm, is deposited on the top of a ...This paper describes a micro thermal shear stress sensor with a cavity underneath, based on vacuum anodic bonding and bulk micromachined technology. A Ti/Pt alloy strip, 2μm×100μm, is deposited on the top of a thin silicon nitride diaphragm and functioned as the thermal sensor element. By using vacuum anodic bonding and bulk-si anisotropic wet etching process instead of the sacrificial-layer technique, a cavity, functioned as the adiabatic vacuum chamber, 200μm×200μm×400μm, is placed between the silicon nitride diaphragm and glass (Corning 7740). This method totally avoid adhesion problem which is a major issue of the sacrificial-layer technique.展开更多
针对热真空环境下的拉力检测,研制了一种基于薄膜溅射工艺的双冗余拉力传感器。主要对溅射薄膜拉力传感器的弹性体结构和应变电阻布局进行了分析设计。针对传感器的零点输出误差设计了零点补偿电路;并对传感器的稳定性处理工艺进行了研...针对热真空环境下的拉力检测,研制了一种基于薄膜溅射工艺的双冗余拉力传感器。主要对溅射薄膜拉力传感器的弹性体结构和应变电阻布局进行了分析设计。针对传感器的零点输出误差设计了零点补偿电路;并对传感器的稳定性处理工艺进行了研究。最终,通过对传感器进行热真空试验,验证了该设计的合理性。实验结果表明,该拉力传感器可在-45℃^+90℃范围内正常工作,灵敏度为13.02 m V/k N,精度高于6‰。展开更多
文摘The monolithic integrated micro sensor is an important direction in the fields of integrated circuits and micro sensors. In this paper,a monolithic thermal vacuum sensor based on a micro-hotplate (MHP) and operating under constant bias voltage conditions was designed. A new monolithic integrating mode was proposed,in which the dielectric and passiva- tion layers in standard CMOS processes were used as sensor structure layers,gate polysilicon as the sacrificial layer,and the second polysilicon layer as the sensor heating resistor. Then, the fabricating processes were designed and the monolithic thermal vacuum sensor was fabricated with a 0. 6μm mixed signal CMOS process followed by sacrificial layer etching technology. The measurement results show that the fabricated monolithic vacuum sensor can measure the pressure range of 2- 10^5 Pa and the output voltage is adjustable.
基金supported by the National Natural Science Foundation of China (No. 90607003).
文摘An on-chip microelectromechanical system was fabricated in a 0.5μm standard CMOS process for gas pressure detection. The sensor was based on a micro-hotplate (MHP) and had been integrated with a rail to rail operational amplifier and an 8-bit successive approximation register (SAR) A/D converter. A tungsten resistor was manufactured on the MHP as the sensing element, and the sacrificial layer of the sensor was made from polysilicon and etched by surface-micromachining technology. The operational amplifier was configured to make the sensor operate in constant current mode. A digital bit stream was provided as the system output. The measurement results demonstrate that the gas pressure sensitive range of the vacuum sensor extends from 1 to 105 Pa. In the gas pressure range from 1 to 100 Pa, the sensitivity of the sensor is 0.23 mV/Pa, the linearity is 4.95%, and the hysteresis is 8.69%. The operational amplifier can drive 200 Ω resistors distortionlessly, and the SAR A/D converter achieves a resolution of 7.4 bit with 100 kHz sample rate. The performance of the operational amplifier and the SAR A/D converter meets the requirements of the sensor system.
基金Project supported by the National Natural Science Foundation of China (Grant No 60576053)Technology Innovation of Chinese Academy of Sciences (Grant No CXJJ-176)
文摘This paper describes a micro thermal shear stress sensor with a cavity underneath, based on vacuum anodic bonding and bulk micromachined technology. A Ti/Pt alloy strip, 2μm×100μm, is deposited on the top of a thin silicon nitride diaphragm and functioned as the thermal sensor element. By using vacuum anodic bonding and bulk-si anisotropic wet etching process instead of the sacrificial-layer technique, a cavity, functioned as the adiabatic vacuum chamber, 200μm×200μm×400μm, is placed between the silicon nitride diaphragm and glass (Corning 7740). This method totally avoid adhesion problem which is a major issue of the sacrificial-layer technique.
文摘针对热真空环境下的拉力检测,研制了一种基于薄膜溅射工艺的双冗余拉力传感器。主要对溅射薄膜拉力传感器的弹性体结构和应变电阻布局进行了分析设计。针对传感器的零点输出误差设计了零点补偿电路;并对传感器的稳定性处理工艺进行了研究。最终,通过对传感器进行热真空试验,验证了该设计的合理性。实验结果表明,该拉力传感器可在-45℃^+90℃范围内正常工作,灵敏度为13.02 m V/k N,精度高于6‰。