电压对铜电化学机械平整化性能影响的实验研究

Experimental Study on Electrochemical Mechanical Planarization Performance of Cu with Different Applied Voltages

在质量分数30%有机膦酸(HEDP)和0.02 mol/L苯骈三氮唑(BTA)电解液中,模拟实验研究静、动态下电压对铜的电化学机械平整化材料去除率和表面质量的影响规律。实验结果表明,铜在30%HEDP+0.02 mol/L BTA电解液中的钝化电压区间为0.2～1.1 V,当阳极电势为0.5 V时,BTA的腐蚀抑制效率接近90%;静、动态下铜的材料去除率均随施加电压的增大而增大,但施加电压过大,铜表面出现腐蚀坑;在不降低表面质量的前提下,当外界施加电压0.5 V时,能较好地平衡电化学作用与机械作用,达到较高的材料去除率。

To explore the mechanism of voltage on material removal rate and surface quality, Cu-ECMP simulating experiments were carried out for rubbing pairs of Si3 NJCu in electrolyte of 30% HEDP ＋ 0. 02 mol/L BTA,in dynamic and static state. Experimental results show that the passivating region is between 0. 2 V and 1.1 V for Cu in electrolyte of 30% HEDP ＋ 0. 02 moL/L BTA. When anode potential is 0. 5 V, the Inhibition Efficiency （IE） even come near to 90%. Material removal rate increases with the increase of voltage in both dynamic and static state. However, the etch pit will apper when voltage is higher. Perfect balance between electrochemical and mechanical action could be obtained when we apply annodic voltage of 0. 5 V, and the Material Removal Rate（MRR） reaches quite high, without reducing the surface quality.