Experimentally Study The Electromechanical Character Of Quantum Well Thin Film Structure

The paper "experimentally study the electromechanical character of quantum well thinfilm structure" mainly research the change of the quantum tunneling electrical signal effectedor induced by mechanical signal, and test the electromechanical coupling effect ofmicro-cavity, bridge and girder stucture composed with quantum well thin film. With thedevelopment of studying on materials science, some new physical characters and physicaleffect have been found in some nano-material. The new nanoelectromachannical devicesbased on the new theory and effect are having been researched. Some new effect (includequantum effect) will appear when the diagnostic dimension of devices reach nanometer level.The effect of electromechanical coupling is very remarkable in the electromachannical system.And the new characters and functions will appear in nano-mechanics.Firstly, the theory of electromechanical character of quantum well thin film is introduced.And the AlAs/GaAs nano-quantum well film was designed and grown by MBE (molecularbeam epitaxy) based on the theory. The resonant tunneling structure based on the nano-filmwas designed and processed, and the macro-accelerometer based on GaAs film was processedfor the first time in our country.The Raman quantitate-stress system was first used in this experiment. And this system hasunique merits: high stress resolution (10MPa) and small focus (less than 1μm). In the paper,two experiment schemes were designed and the electromechanical character of resonanttunneling structure and macro-accelerometer was roundly tested. In addition, the consistencyand temperature character of resonant tunneling structure was researched. All theseexperiments can provide sufficient experiment data for application of quantum well thin film.By experiment, some new phenomena were put forward: ①the piezoresistive sensitivityof macro-accelerometer based on the quantum well thin film is more than one order ofmagnitude higher than that of silicon piezoresistor, ②the relation between electromechanicalcharacter of resonant tunneling structure, macro-accelerometer and the direction of pressurewas found, and the relation was simulated and validated in theory.In conclusion, this experiment research provides many effective experiment data forapplication and technics of quantum well thin film, validates nanoelectromechanical effectand the feasibility of nanoelectromechanical system based on the quantum well thin film. So,this experiment research is very significant.