铝刻蚀液磷酸浓度变化及TRIZ解决方案

H;PO;Conentration Change in Aluminum Etchant and Its TRIZ Solution

铝刻蚀液由硝酸、醋酸、磷酸混合组成,各酸液浓度变化会对刻蚀产生影响。量产过程中,设备对硝酸和醋酸进行单酸补给,保持其浓度稳定。但磷酸不补给,其浓度会逐渐下降。该文结合铝刻蚀产线,研究了单酸补给开启与关闭情况下磷酸浓度对刻蚀程度的影响;然后结合TRIZ,对量产条件下磷酸浓度下降现象进行分析,并输出解决方案。实验结果表明:单酸补给关闭,硝酸、醋酸逐渐消耗,刻蚀能力降低;当单酸补给开启,硝酸和醋酸浓度稳定,磷酸浓度逐渐下降,刻蚀能力也降低,这是因为补给的硝酸、醋酸含有水,水稀释磷酸造成其浓度下降。刻蚀能力下降会导致金属残留,进而造成良率损伤。结合TRIZ方案,可以通过加大刻蚀区间排气、调整刻蚀出口空气帘流速、根据药液使用时间调整刻蚀产品类型等措施来规避磷酸浓度下降对刻蚀造成的影响。此项研究,为产品良率提升提供参考。

The aluminum etchant is a mixture composed of nitric acid,acetic acid,and phosphoric acid,and concentration changes of each acid in etchant will affect the etching.In mass production,the equipment replenishes nitric acid and acetic acid to keep their concentrations stable,while the phosphoric acid concentration will gradually decrease without replenishment.In this paper,the influence of phosphoric acid concentration on the etching degree was studied when the monoacid supply is turned on and off.Then combined with TRIZ,the phosphoric acid concentration decline was analyzed.At last,the TRIZ solution was output to avoid the decrease in phosphoric acid concentration.The results show that nitric acid and acetic acid are gradually consumed,and the etching ability is reduced when the monoacid supply is turned off.However,when the monoacid supply is turned on,the concentration of nitric acid and acetic acid is stable,and the concentration of phosphoric acid gradually decreases,and the etching ability is also reduced.The supplied nitric acid and acetic acid contain water,which dilutes the phosphoric acid,causing the concentration of phosphoric acid to decrease.In addition,decreased etching ability will lead to metal residues,which in turn will cause yield damage.Combined with the TRIZ solution,measures such as increasing the exhaust of the etching chamber,decreasing flow rate of air curtain at the etching outlet,and adjusting the product type according to the use time of the etchant,can avoid the influence of the drop in the concentration of phosphoric acid.This research provides a reference for product yield improvement.