A 3D measurement system of micro organization based on two-ray-path scanning was developed. This article introduced
the principle and setup of the system. Experiments were carried out to measure the three-dimensional shape of some
micro organizations. The results showed that this system could measure accurately not only the thickness of each part of
the micro organization, but also can show its three-dimensional shape quickly and accurately. The vertical error was less
than 2 μm. This system has advantages of compact structure, accurate detection, and high reliability, and can realize
nondestructive measurement of micro organization.
In this article, an innovative micro-actuator based on photo-thermal heating is introduced. The basic ideas are to apply a
new way to get large actuation power from laser source. When a beam of laser irradiates a thin sheet, the sheet
temperature increases and volume expands. Besides irradiation laser power, convection coefficient and the parameters of
sheet material, the length-width ratio of sheet also influences the heating process. Applying this characteristic, an
asymmetric photo-thermal actuator was manufactured by the excimer laser micromaching system. Steady-state thermal
analysis is presented. Feasibility experiments with a laser diode (655 nm) as the power source were carried out, and the
data of deflection have been measured under different laser power. The experiment results prove the availability of these
novel photo-thermal micro-actuators, and demonstrate that the deflection can be 11.8 μm at 10 mW laser power. This
mirco-actuator doesn't need of the old power supply modes of external electric wire or small battery, and can be operated
in non-focused uniform irradiation, so it has more mobility and can be controlled remotely. Furthermore, this actuator
can be applied in many special environments.
In view of the fact that the application field of a dual tunneling-unit scanning tunneling microscope (DTU-STM) was strongly limited by sample conductivity, a dual imaging unit atomic force microscope (DIU-AFM) was developed for wide-range nano-metrology. A periodic grating is employed as a reference sample. The DIU-AFM simultaneously scans the grating and a test sample by using one single XY scanner. Their images thus have the same lateral size, and the length of the test sample image can be precisely measured by counting the number of periodic features of the reference grating. We further developed a new method of implementing wide-range nano-metrology. By alternatively moving the XY scanner in the X direction using a step motor, a series of pairs of images are obtained and can be spliced into two wide-range reference and test ones, respectively. Again, the two spliced images are of the same size, and the length of test image can be measured based on the reference grating features. In this way, wide-range metrology with nanometer order accuracy is successfully realized.
In this paper, a new type of AFM scanning in liquid is developed. It circumvents the limitations of scanning electron microscopy by working in-situ, facilitating real-time studies of iron corrosion. We briefly introduce the structure of the AFM probe, liquid cell, scanning and photoelectronic feedback control system for image scanning and processing in liquid. By using the AFM scanning in liquid, a process of metal corrosion in liquid circumstance can be observed and the real-time images of the sample surface were successfully gained. The results indicated that although corrosion generally appears to be a macroscopic phenomenon, it typically begins at the atomic or near atomic level. And the experiments also show that this system could avoid the effect of surface tension and vibration on AFM images and was not restricted by sample's size and weight. It is of high repeatability, reliable stability and ideal contrast for image acquisition, and has a resolution of better than 1nm, covering a scan range from 100 nm x 100 nm to 10 mm x 10 mm.
A new type of horizontal atomic force microscope (AFM) is developed for applications in nanotechnology. This article provides the basic principle and setup of the horizontal AFM. The light pressure of laser and the gravity exerting on the micro-cantilever was first conducted, conceiving a method to remove the effects of these factors on the interaction mechanism of atomic force and the performance of AFM. It has a horizontally designed probe unit and owns a particular path of optical beam deflection method for the measurement of cantilever’s displacement with its minimized structure. For the purpose of precise and effective imaging for different samples, we introduced a novel method to adjust the setpoint of imaging force and provided the calculative formula. A new feedback controlling theory and method of horizontal AFM was also advanced in order to develop an effective, steady and optimum feedback controlling system. Experiments show that the horizontal AFM is of high repeatability, reliable stability and ideal contrast for image acquisition. The horizontal and vertical resolutions of the system are 3 nm and 1 nm, respectively, with a maximum scan range of 10 mm´ 10 mm. These remarkable characteristics enable the AFM system to be widely applied in the fields of nanotechnology.
To implement electrostatic suspension with optoelectronic feedback control (ESOFC), real-time detection of the gap between the suspended object and the electrode is needed to determine the position of the object. In this article, we designed a laser gap sensor based on the principle of laser trigonometry, and developed a novel method to calibrate the nonlinearity of the conventional laser trigonometry by using a simple nonlinearity-correction circuit. Experiments show that this optimized sensor has an accuracy better than 7 μm when controlling the gap within the range from -2.0 mm to +2.0 mm, which meets the need of our ESOFC system quite well. Furthermore, it can also be widely applied in other displacement-detecting systems.
Using the numerical analysis method, the mechanism of the surface acoustic wave (SAW) motor is further discussed, the performances of the SAW motor under different slider and stator contact conditions are examined, and many factors that affect the efficiency of the SAW motor are introduced. In addition, the design of SAW motor with power circulation structure is illustrated. Experiments show that the efficiency of the SAW motor increases, and the threshold driving voltage of the SAW motor reduces.