Abstract:
Due to the characteristics of high brittleness and low fracture toughness of monocrystalline silicon, its high precision and high-quality cutting have great challenges. Aiming at the urgent need of wafer cutting with high efficiency, this paper investigates the influence law of different laser processes on the size of the groove and the machining affected zone of laser cutting. The experimental results show that when laser cutting monocrystalline silicon, in addition to generating a groove, there will also be a machining affected zone on both sides of the groove and the size of both will directly affect the cutting quality. After wiping the thermal products generated by cutting on the material surface, the machining affected zone and the recast layer in the cutting seam can basically be eliminated to generate a wider cutting seam and the surface after wiping is basically the same as that before cutting. Increasing the laser cutting times will increase the width of the material\'s machining affected zone and the groove width after chip removal. When the cutting times are less than 80, increasing the cutting times will increase the groove width at the same time; but, after the cutting times exceed 80, the groove width abruptly decreases and then slowly increases. In addition, the lower the laser scanning speed, the larger the width of the material\'s machining affected zone and the width of the groove after chip removal. The increase in laser frequency will increase the crack width and the crack width after chip removal but decrease the machining affected zone width. The laser pulse width has a certain effect on the cutting quality but it does not show regularity. When the pulse width is 0.3 ns the cutting quality is the best and when the pulse width is 0.15 ns the cutting quality is the worst.
摘要:
由于单晶硅的高脆性和低断裂韧性的特点,其高精度和高质量的切割有很大的挑战。针对晶圆切割高效率的迫切需要,本文研究了不同激光工艺对激光切割坡口尺寸和加工影响区的影响规律。实验结果表明,激光切割单晶硅时,除了产生凹槽,在坡口两侧也会有一个加工影响区,两者的大小将直接影响到切削质量。擦拭材料表面切割产生的热产物后,基本可以消除切缝中的加工影响区和重铸层,以产生更宽的切缝,擦拭后的表面与切割前的表面基本相同。增加激光切割次数将增加材料的加工影响区的宽度和切屑去除后的凹槽宽度。当切割次数小于80时,增加切割次数将同时增加凹槽宽度;但是,切割次数超过80次后,凹槽宽度突然减小,然后缓慢增加。此外,激光扫描速度越低,切屑去除后,材料加工影响区的宽度和凹槽的宽度越大。激光频率的增加会增加裂纹宽度和切屑去除后的裂纹宽度,但会降低加工影响区的宽度。激光脉冲宽度对切割质量有一定的影响,但没有表现出规律性。当脉冲宽度为0.3ns时,切割质量最好,而当脉冲宽度为0.15ns时,切割质量最差。