A Research And Development Of Multi-wire Saw Technique With Ultrasonic Vibration And Its Machining Mechanism

With the rapid development of solar cell and large scale integrated circuits industry, the multi-wire saw technique needs increasingly high demands, especially the widespread application of the large diameter and super large diameter monocrystalline silicon chip in the process of integrated circuit production. The quality of sliced workpiece directly influences the efficiency of follow-up processing and the yield of silicon wafer. Hence, it has an important realistic meaning to get better sliced quality by seeking new auxiliary processing techniques and applied to multi-wire saw.According to the current problems of the broken wires during multiple wire sawing processing and the efficiency and quality of cutting slices, this paper intensive studied ultrasonic machining principle and its application effect in multi-wire saws. The innovative design was presented to use ultrasonic vibration on worktable. Combined multi-wire saw with ultrasonic machining principle, ultrasonic vibration acts on the vertical direction of worktable, studied the impact of ultrasonic vibration in taking slurry and machining slice efficiency.The ultrasonic assisted multi-wire sawing technology is studied in this paper by means of theoretical analysis, ANSYS simulation, equipment development and experimental analysis. The main contents and achievements of the paper concluded as follows:(1)According to the ultrasonic vibration theory and multi-wire sawing theory, deduced the material removal rate by simplifying the model. It is theoretical proved that the material removal rate is higher under the influence of ultrasonic vibration by comparing the material removal rate between the ultrasonic vibration effect and none ultrasonic vibration effect.(2)Analysis the cutting wire model under the effect of ultrasonic vibration, and studied the resonance frequency and transient dynamic state of cutting wire, which provided the theoretical foundation for ultrasonic vibration applies to multi-wire sawing technique.(3)Based on the theoretical analysis, developed the ultrasonic vibration platform and multi-wire cutting simulation device.(4)Tested the time domain vibration state on ultrasonic vibration platform and studied its machining factors(output of ultrasonic power, linear velocity and feed rate).(5)Analysis the cutting line mode under the ultrasonic vibration effect with high-speed cameras, studied the different machining factors(output of ultrasonic power, linear velocity).(6)Studied the taking slurry and machining slice efficiency using high-speed cameras during the free abrasive wire saw experiment. Compared the silicon wafer cutting efficiency under the ultrasonic vibration with the ordinary one, which provide the data support for ultrasonic vibration applies to multi-wire saw technique.It is of great significance to study the ultrasonic assisted multi-wire sawing technique. As the wafer cutting technique has been the important technical link of silicon wafer manufacturing industry, and directly influences the development of countries in the field of the silicon chips manufacture.