Dissolution of Mo/Al Bilayers in Phosphoric Acid

Bulletin of the Korean chemical society

Seung whan Chon¹  In Sung Kim¹  Il Cheol Jeon¹  Ky Sub Kim¹ 

关键词: Wet etching;    Tafel plot;    Quartz crystal microbalance;    SEM;    HNO3;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

In the phosphoric acid based etchant, the dissolution rates of Mo films were measured by microgravimetry and the corrosion potentials of Mo and Al were estimated by Tafel plot method with various concentrations of nitric acid. Dissolution rate of Mo increased with the nitric acid concentration and reached a limiting value at high concentration of nitric acid in ambient condition. Corrosion potentials of Mo and Al shifted to positive direction and the difference between potentials of both metals was about 1,100 mV and 1,200 mV with 1% and above 4% of HNO3, respectively. For a Mo/Al bilayers, the dissolution rate inversion is the main reason for good taper angle in shower etching process. Taper angles are observed by scanning electron microscope (SEM) after wet etching process for Mo/Al layered films with different concentrations of HNO3. In the etch side profile, it was found that Al corroded faster than Mo below 4% of HNO3 in dip etching process, however, Mo corroded faster above 4%. Trend for variation of taper angle of etched side of Mo/Al layered film can be explained by considering the effect corrosion rates of both metals with various concentrations of HNO3.

【 授权许可】

Unknown