高线速下碳化硅单晶的快速平坦化切割

Rapid Slicing SiC Ingots with Low Warp at High Velocity

碳化硅单晶材料硬度很高,用传统的切片方式难以加工、效率低下,多线切割是加工硬脆材料的有效方式,文章通过使用电镀金刚石线多线切割设备,进行了高线速度条件下快速碳化硅单晶平坦化切片实验。为提高碳化硅切割效率,通过提高金刚石线速度,成功实现了用5.5小时进行4英寸碳化硅晶锭的切割,并将切割6英寸晶锭时间缩短至12小时左右。同时,为减小切割片翘曲度,进行了4英寸和6英寸碳化硅晶锭的切割试验,证明切割线速度直接影响切割片的翘曲度:随着线速度增大,晶片翘曲度减小。最后,研究了线速度和金刚石浓度对切割片表面的影响,发现提高线速度和使用高金刚石浓度的金刚石线都可使切割导致的损伤层减小。

The hardness of silicon carbide single crystal material is very high. It is difficult to process the material by traditional slicing method and its efficiency is low. The Multi-wire cutting is an effective way to process hard and brittle materials. In this paper, the experiment of slicing silicon carbide single crystal planarly at high linear speed was carried out by using electroplated diamond wire multi-wire cutting equipment. In order to improve the cutting efficiency, the cutting of 4 inches silicon carbide ingot in 5.5 hours was successfully realized by increasing the linear speed of diamond, and the cutting time of 6 inches silicon carbide ingot was shortened to about 12 hours. At the same time, in order to reduce the warpage of the cutting piece, the cutting experiments of 4-inch and 6-inch silicon carbide ingots have been carried out. It is proved that the cutting linear speed directly affected the warpage of the cutting piece: with the increase of the linear speed, the wafer warpage decreased. Finally, the effects of linear velocity and diamond concentration on the surface of the cutting chip were studied. It was found that increasing linear velocity and using diamond wire with high diamond concentration could reduce the damage layer caused by cutting.