Development of a two-dimensional ultrasonic vibration assisted grinding technique of monocrystal silicon

Based on the characteristics of higher machining efficiency and higher surface quality of ultrasonic vibration grinding, a two-dimensional ultrasonic vibration grinding of monocrystal silicon technique is achieved by designing elliptical vibrator with longitudinal mode and bending mode. The measurement results on the vibration characteristics of vibrator show that shape and amplitude of elliptical vibration can be modulated by changing voltage amplitude and phase difference between the piezoelectric ceramics electrodes. The grinding experimental results show that under the elliptic ultrasonic vibration assistance, grinding forces are reduced largely, the surface roughness is decreased significantly, the surface quality is improved obviously, and moreover the percentage of ductile-mode removal material increases. These indicate that high efficiency and high surface quality machining of monocrystal silicon can be achieved with elliptic vibration assisted grinding.