| Chemical mechanical polishing (CMP) is now the most practical method of brittle materials, and widely used in microelectronics and optoelectronics. Since the first application in integrated circuit chip by IBM in the 80s of last century, it has been perfected through constant exploration and mechanism research. However traditional CMP is in low utilization factor and not easy to control. It also cause environment pollution. In response to these problems and for the purpose of fine material remove, the method of ultrasonic subtle atomization—chemical mechanical polishing is proposed with the help of China Postdoctoral Science Foundation and Natural Science Foundation of Jiangsu Province.The method of chemical mechanical polishing using slurry which is ultrasonic subtle atomized is proposed to use specific frequency ultrasonic to atomize special slurry and get uniform micron-sized droplets whose diameters are between 5u.m and 15um. The droplets are imported to polished/polishing interface by special way, and finally the specimen gets the surface which is super-smooth in nanometer without damage after a series of chemical and mechanical reactions.This article describes the confirmation of the experimental system's process, the laboratory equipments' placement, the design of the polishing experimental system and the solution of key technologies. The polishing machine is transformed in order to prevent it from corrosion. Organic glass is used to seal the polish reaction in a certain space. Frame is built on the glass, and polar is used to achieve the three dimensional precise location of the nozzle. Negative pressure is to import the droplets to the polishing interface, so the droplets can be uniform distributed and effective used. Shunt is used to adjust the deionized water flow. The pressure is adjusted by the pressure piece. Slurry is filtered and recycled by two grade filtration equipment.In this paper, pressure and three-dimensional coordinates of the nozzle were orthogonal tested, and the result shows: the ultrasonic subtle atomization experiment system can realize ultrasonic subtle atomization. Surface roughness after ultrasonic subtle atomization CMP is in the same grade as the surface roughness after traditional CMP, but amount of slurry in ultrasonic subtle atomization CMP was only about 1/10 compared to traditional CMP. In this experiment the maximum of MMR was 113.734nm/min while pressure was 10Psi, nozzle height was 5mm, the distance between polish pad center and nozzle center was 30mm and nozzle angle was -30°. The distance between polish pad center and nozzle center has the most significant effect to MMR in the four selected parameters.Five parameters which are polishing machine speed, nozzle height, pressure, nozzle angle and nozzle radius are researched alone. It is concluded that: the material removal rate increases with polishing machine speed and the pressure while the nozzle height, nozzle radius and nozzle angle decreases. The specimen surface is observed by CSPM5000 scanning probe microscope system. Surface roughness are all below lOnm, and have reached the magnitude of the surface roughness in traditional CMP. There is no obvious change in surface roughness. So it can considered the mechanical action is dominant in the ultrasonic subtle atomization CMP experiments. The large size of particle in the slurry is an important factor to influence surface roughness.
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