Developing Of Diamond Thin Film Pressure Sensor

At the time being, much effort has been made on the application of the semiconductor diamond thin film devices, and progresses have been made on its electrics application because the problem of doping art is well resolved. Now it has been confirmed that doped diamond thin film can be used as semiconductor device and can possibly serve as a new generation of semiconductor material to replace silicon, and it can be prepared to be sensor devices with high reliability, high temperature-resistance and radiation-resistance for its excellent properties. After the success of temperature and pressure sensor in America, the practicality of diamond film are now focusing on high reliability and sensitivity at high temperature, erosion and radiation. This is the breakthrough of the soaring of the diamond thin film based functional devices now.The pressure - resistance mechanism of the B doped diamond thin film is discussed from the assorted effective factors of the conductance of semiconductor, combining with the band theory of semiconductor, theory of deforming potentiality, valence band splitting model and polymer-crystal model of Mayadas-Shatzkes.The development of diamond thin film pressure sensor CMOS chip:Using the "non-sub crystal and non-deflective voltage standard single crystal deposition " manner mentioned in this article, even and smooth pure-diamond thin film with 20-30 urn grows in the fixed direction on the polished silicon base by the hot-fuse method. After the erosion of the silicon base, the surface of diamond thin film on the interface of the silicon base is required to be smooth and even without polishing. This is critical to gain even stress after the bearing film being pressed.On the even and smooth pure diamond, covered filmed optional growing technology is used to direction-fixed deposit four B doped diamond resistance to form Wegence electric bridge to prepare the self-compensated pressure sensor CMOS chip.The finite-unit theory and ANSYS programs in the value calculation are used to simulate the three -dimensional distribution of stress field of the sensor bearing diamond film, which is firmly fixed with four B doped resistance, in order to make sure the optimal size, shape, position and arrangement manner of B doped pressure sensitive resistance to realize the optimal design of CMOS chip.Upon the preparation of intellectualized diamond thin film sensor circuit, the pressure-voltage curve is measured at different temperature. Intellectualized diamond thin film sensor samples are made by adopting the non-liner self-correct technique to overcome the non-liner of pressure -voltage and the temperature effect of the voltage signal output. The accurate pressure signal is drawn out from the co-formed pressure and voltage output. The creative points:1. theoretical aspects: stress class 1 inducing the change of stress class 2 is mainly used to analyze the effect of pressure -resistance of B doped diamond thin film, it has not been reported yet. This theory can also be used in the study of mechanism of semiconductor pressure resistance of ploy-crystal and single -crystal, and can directly instruct the developing art of thin film conductor devices.2. Experimental aspects: non-sub crystal and non-deflective voltage standard single crystal deposition manner is put forward. Depositing dense and smooth diamond film and B doped diamond resistance on the smooth silicon base were probed to make even distribution of stress and to enhance the stability and the consistence. This has not been reported yet (the patent has been applied).Design: The finite-unit theory and ANSYS programs in the value calculation are used to simulate the three -dimensional distribution of stress field of the sensor bearing diamond film, which is firmly fixed with four B doped resistance. The circle angle of the resistance band is put forward and the optional shape of the pressure sistitive resistance is made sure. This has not been reported yet.What is reported is that: simulating the three -dimensional distribution of str...