Papers by Author: Qing An Huang

Abstract: This paper presents a novel capacitive sensor for real-time monitoring of temperature in the silicone oil fan clutch. The structure of the temperature sensor is designed and fabricated by the Silicon-On-Glass (SOG) process based on the bonding technology. The silicone oil is designed as the temperature sensing materials in the capacitive sensor. The capacitance of the embedded sensor is changing with respect to temperature of the silicone oil fan clutch. Experimental results show that the sensor provides a sensitivity of 27.3fF/°C in the -30 to 40°C range, 58.2fF/°C in the 50 to 110°C rang. It is also demonstrated that the temperature sensitive capacitor can be integrated with a copper inductance antenna and tests as a passive wireless temperature sensor. The resonant frequency of the inductor-capacitor (LC) resonator changes with respect to the changing capacitance. Then temperature changes can be remotely determined towards a frequency spectrum study. Experimental results show that the LC type passive wireless sensor provides a sensitivity of 6.35kHz/°C in the -30 to 110°C range.

Abstract: In this paper, a direct and simple method to characterize the elastic modulus of individual layers for composite films by in situ measuring of MEMS test structures is presented. The structure is composed of a set of microactuators which contains a rigid plate with two supporting composite beams. A model is developed to describe analytically the relationship between the force and the deflection of microactuators by electrostatic measurements, and the elastic modulus of multi-layered beams with different widths are evaluated. FEM simulations are implemented to validate the accuracy of the relationship between the on-load voltage and the capacitance between the microactuator and the electrode on the substrate. Test structures are fabricated using CMOS-MEMS process and experiments are to be carried out soon.

Abstract: In this paper, a simulation model is proposed to describe CH₄ adsorption-induced curvature of a nanocantilever, based on the energy transfer between potential energy of adsorbates and elastic energy of the bending cantilever. For most cantilever sensors, the basic structure is a silicon beam coated with a metal layer on the top, and aluminum is chosen here. Because the native oxide is usually formed during the fabrication of silicon beams, we have to describe the effect of native oxide on the elastic modulus of the silicon nanobeam in this model based on the semi-continuum method. This model gives a way to predict the curvature of the composite cantilever with native oxide when adsorbing a single layer of CH₄ molecules.