| dc.description.abstract | High precision micro-holes and micro slits are an important target that can be made in the micro-electro-mechanical systems (MEMS). Therefore, the main purpose of this thesis is to develop an economical and effective method to produce high accuracy micro-holes and micro slits. A compound or batch mode method was introduced to our researches. Furthermore, the high precision micro-holes were successfully fabricated in the metal or glass by the compound method, and the batch mode method was an efficient method to manufacture a micro slit die. A micro heat sink can be made using micro slit die in the plastic deformation manner.
In these experiments, an electrode was pruned to appropriate micro size by an electrical discharge grinding mechanism, first. Then a micro-hole or a semi-sphere concave hole in a metal plate was drilled using this electrode in micro EDM (MEDM). Finally, a micro ultrasonic grinding (MUG) or magnetic polishing was applying to burnish these micro-holes. Furthermore, the electrode was also utilized as a cutting tool when the micro-hole was fabricated by ultrasonic machining equipment in a small glass plate. In addition, an assembly electrode was used to make a micro slit die via MEDM in a tungsten carbide plate. Then combining with the pressing or scraping method, micro heat sinks could be produced applying the micro slit die.
Combining with MEDM and MUG to fabricate the micro-hole with diameter 100 ?m or square lateral length 100 ?m, a high precision micro-hole would be obtained at appropriate abrasive concentration, ultrasonic amplitude, rotating speed and slow feed rate. The straight grinding tool had better precision improved rate of micro-hole between entrance and exit (PIREE) than the step grinding tool in the MUG process. PIREE would reach 60% at suitable ultrasonic parameters. However, the step grinding tool would get the good surface roughness. The micro-hole with thickness 500??m and diameter 150 ?m in the Pyrex glass was drilled by micro ultrasonic machining method (MUSM). The diameter difference between entrance and exit would reach 2 ?m if appropriate abrasive concentration, ultrasonic amplitude, rotating speed and slow feed rate were used. The semi-sphere micro-hole in taper thin rod with diameter 150 ?m could be manufactured, combining with MEDM and micro grinding process. The burr attached in the micro-hole edge could be removed and the thin rod outside surface would be smoothed by magnetic polishing manner. In addition, the batch mode production of micro slits die would be carried out by assembly copper foils in MEDM. The micro heat sink would be fabricated using micro slits die at plastic deformation machining. However, manufacturing of micro slits die in MEDM needed to cooperate with the dielectric flushing way to find the good micro fins shape. During the oxygen combustion-supporting and electrolytic effect, the MEDM efficiency would increased fast when the distill water was utilized as dielectric. The micro slit die fabricating speed in distill water would fast 5 time of the kerosene. The micro fin shape was not control easily in MEDM because of the fast electrode abrasion. | en_US |