超高导热陶瓷复频超声加工的基础试验研究

The Basic Experimental Studies on Multi-Frequency Ultrasonic Machining of the Ultra-High Thermal Conductivity Ceramics

超高导热陶瓷基板作为新一代大规模集成电路的理想封装材料,其硬脆特性为加工带来了极大的困难。在工程陶瓷传统超声加工理论的基础上,针对因超声波发生器功率有限造成的传统单频超声加工振幅难以提高的问题,通过添加自由质量块引入低频大振幅振动的方法,实现了复频超声加工;针对因自由质量块的非正常碰撞造成复频超声加工单元频率不稳定的问题,对自由质量块进行优化设计,有效提高了装置的稳定性;针对因低频大振幅振动引入造成工件出入口处崩边现象加剧的问题,设计了自由质量块捕捉装置,搭建了“刚柔并济”的复频超声加工试验系统;针对影响其加工效率的工艺参数进行了试验研究,试验结果表明:与传统超声加工方法相比,在合理选择自由质量块和轴向静压力的条件下,该方法在保证加工精度的同时,可大幅提高加工效率。

Ultra-high thermal conductivity ceramic substrate is an ideal packaging material for a new generation of large-scale integrated circuits,and its hard and brittle characteristics bring great difficulties to processing.Based on the traditional ultrasonic machining theory of engineering ceramics,aiming at the problem that the amplitude of traditional single-frequency ultrasonic machining is difficult to increase,due to the limitation of the power of the ultrasonic generator,the method of introducing low-frequency large-amplitude vibration is adding a free mass block to realize the multi-frequency ultrasonic machining.Due to the abnormal collision of the free mass,the frequency of the multi-frequency ultrasonic machining unit is unstable.the free mass block is optimized and the stability of the device is effectively improved.Due to the introduction of low-frequency and large-amplitude vibration,the phenomenon of chipping at the entrance and exit of the workpiece is intensified,thus a free mass block capture device is designed,and a multi-frequency ultrasonic machining test system of“rigid and flexible”is built.The experimental results of the process parameters affecting the processing efficiency are tested.The test results show that compared with the traditional ultrasonic machining method,in the case of reasonable selection of free mass and axial static pressure,the method can greatly improve the processing efficiency while ensuring the processing precision.