Study On A New Method Of Microstructure Manufacturing Using Capillary Microprobe

Micro/nano-technology is a newly developed interdisciplinary subject in recent years, as one of its important branches, micro-nanofabrication technology is applied widely in a lot of areas. Traditional micro-nanofabrication technologies include bulk micromachining technology, surface micromachining technology, LIGA (X-ray deep lithography, electroform molding, plastic molding) technology, bonding technology and sacrificial layer technology, etc. The emergence and evolution of these micro-nanofabrication technologies promoted microelectronics and photonics technology's development greatly. However, these technologies had many disadvantage, for example, needed expensive equipment, complex steps, and long machining cycle, which limited the further development of micro/nano-technology. Therefore, we proposed a new technique of rapid microstructure preparation based on localized electrochemical deposition (LECD) with a special designed capillary microprobe and established a novel microstructure fabrication and monitoring system which could fabricate micro structures efficiently, rapidly and low cost.In this project, we theoretically analyzed the new method, developed the system and carried out some experimental studies. The innovations and research work as follows:We brought forward a new method of microstructure fabrication based on capillary microprobe. We designed a new microprobe, which is made by Pt-Ir wire directly inserted into a glass micropipette. The new microprobe could be single one or several micropipettes arrayed together. We sharpened the end of Pt-Ir wire, and placed it at the same plane with the bottom of micropipette. Using this new microprobe, microstructure with great uniformity could be fabricated based on LECD technology.We developed a microstructure fabrication and monitoring system utilizing capillary microprobe. The system includes the core unit of microstructure fabrication, step scan and mobile control system, CCD monitoring module and computer control system. During the deposition processing, the microscope process can be monitored in real-time using CCD monitoring module. So it can be easily for us to observe the phenomenon of microstructure deposition caused by electrochemical reaction. The system has low cost, simple operation, the module can be strong substitution, etc., it can realize microstructure quickly and easily fabrication.We designed a step mobile control software system with consummate function, friendly interface, and abundant control parameter. The control software had the function of controlling step direction, adjusting step speed and setting step count. Via setting different parameter and controlling the movement of two-dimensional step scanning system, microstructure with different width and aspect ratio could be fabricated conveniently.In the end, using this microstructure fabrication and monitoring system, we have done a lot of experiments. By adjusting the composition and concentration of electrolyte, current density, and step-moving speed, we gained a great deal of microstructures such as point, line and micro columns with great aspect ratio (height/diameter). Several copper micro columns are obtained which are growing at the same time. Moreover, lines with micro width are also fabricated on ITO film. The experimental results well verify that this new method and its system is feasible and accuracy.