Study on the degradation of wire bonding wedges and a proposed method for the prolongation of wedge service life

Abstract

Bonding wedges are one of the most important tools in wire bonding process. The performance of bonding wedge determines the flexibility, reliability, cost of bonding process. The degradation of bonding wedges occurs frequently during bonding process which results in bonding failure and reliability problems. In this paper, common bonding tools were introduced. The degradation phenomenon of bonding wedges were studied using repeated experiments. The resultant on wedge tip induced degradation was analyzed. A cleaning tool tray and an ultrasonic cleaning method using sodium hydroxide were proposed to remove the resultant. The results showed that the degradation without obvious wear on wedge tip was caused by the resultant containing additional silicon which came from gold wire. By using cleaning process when degradation occurred due to resultant, the wedge could work properly until wear by nature.