Study Of Nano Level Vibration Detection Theory And Technology Based On The Tunneling Effect

Scanning tunneling microscopy is one of the advantageous instruments for nano measurement study, instrument precision and repetition are two important indexes. Even if using the vibration-isolation platform, it is easily affected by the outer random vibration in the course of measurement and the measuring repetition is not well, because the tunneling gap only has several nanometers or less. The vibration has become one of the obstacles to improve the nano measurement precision. Now, the anti-vibration, vibration isolation, vibration compensation are one branch in the nano measurement field, especially it has great important significance in the nano subject, especially along with the development of the nano test technology.The vibration has great influence on the measuring result of STM, considering inversely, STM is very sensitive to the vibration in the measurement. Using this measuring principle, the nano level vibration can be detected and compensated for the error of STM by vibration.The main research works are listed as follows:1. The principle of nano level vibration detection is studied primitively and the method of nano level vibration detection based on the tunneling effect is put forward. This method is fit for online detection in STM working state and it can realize the complete compensation because the same measuring principle.2. The nano level vibration detection system using the double micro-motion stage is designed, two stage have nano level resolution in the horizontal and vertical direction respectively. Using this system, it can ensure the measurement of nano level vibration. The system is stable and rigid, and it accords with Abbe error design principle.3. The detection circuit suitable for the measurement of tunneling current is designed. According to the character of the detection circuit, the measuring head is designed to solve the circuit shield problem and the tip fixing. The measuring experiments of the static and dynamic character of tunneling current are carried out and the static character is calibrated. The resolution of the circuit is 1pA.4. The detection experiments of nano level vibration are made and the response of the system to the nano level vibration is available in the different frequency, different amplitude and different signal. The experiments show the output response also has regular change under changeable frequency and amplitude.5. The source of the system error is analyzed and the improved and settling method is put forward. All of this will make a foundation for the design of micro sensor for nano level vibration.