陶瓷封装VDMOS功率器件粗铝丝超声键合工艺研究

Research on Ultrasonic Bonding Process of Thick Aluminum Wire for Ceramic Package VDMOS Power Devices

陶瓷封装垂直导电双扩散场效应管(VDMOS)功率器件广泛地应用在新能源设备、汽车电子和其他工业领域。为了满足VDMOS器件的高可靠性使用要求,有必要对VDMOS粗铝丝超声键合工艺展开深入研究。通过工艺窗口定位及三因素三水平正交实验法探究粗铝丝超声键合工艺参数对键合点强度的影响情况。实验数据表明,超声功率是键合强度的主导因素,这是因为超声功率提供键合点金属扩散所需的绝大部分能量。此外,超声时间及键合压力为键合点金属扩散区的形成提供生长时间及生长环境,同样直接影响键合点的强度。分析结果表明,在满足一定推力要求的条件下,使用最优工艺参数作业能够得到面积更小的键合点,这可以增加芯片的有效利用面积,从而为高密度集成及多管脚引出提供技术支撑。

Ceramic package vertical conductive double diffusion field effect transistor(VDMOS)power devices are widely used in new energy equipment,automotive electronics and other industrial fields.In order to meet the high reliability requirements of VDMOS devices,it is necessary to conduct an in-depth research on the ultrasonic bonding process of VDMOS coarse aluminum wires.The influence of process parameters of ultrasonic bonding of thick aluminum wire on the strength of the bond point is explored through process window positioning and three-factor three-level orthogonal experimental method.Experimental data shows that ultrasonic power is the dominant factor in bond strength because ultrasonic power provides the vast majority of the energy required for metal diffusion at the bonding point.In addition,the ultrasonic time and bonding pressure provide the growth time and growth environment for the formation of the metal diffusion zone at the bonding point,which also directly affects the strength of the bonding point.The analysis results show that under the condition of meeting certain thrust requirements,the use of optimal process parameters can obtain bonding points with a smaller area,which can increase the effective utilization area of the chip,thus providing technical support for high-density integration and multi-pin lead-out.