| 초록 |
The effects of thiourea (TU) on Ag electroplating for ultra large-scale integrated (ULSI) circuits interconnection were experimented. To remove silver sulfide and the other contaminations, the diluted nitric acid was used in the pretreatment process. For successfully deposition on the patterned wafer, the rms roughness was momentous issue. As a result of addition of small amount of TU, the rms surface roughness of electroplated Ag film was decreased about 40 %. Also the deposition rate was decreased. To reduce the resistivity and enhance the adhesion of Ag electroplated film, we performed annealing process at 350℃ in a nitrogen atmosphere. Finally, Ag film was successfully electroplated on the patterned wafer which has aspect ratio from 0.93 to 2.1. |
