Investigation of superfilling and electrical characteristics in low-impurity-incorporated Cu metallization

Abstract

Complete filling of 0.13-mum vias and deposition of Cu with a low resistivity of about 2.3 muOmega(.)cm were obtained using an electrolyte with 2-aminobenzothiazole (2ABT) as the filling promoter. Due to the moderate charge transfer polarization characteristic realized by the addition of 2ABT, the film resistivity and the activation energy for thermal grain growth were similar to those for electrolytes without it. After rapid thermal annealing (RTA) at 400degreesC for 30 s, the resistivity was further reduced to similar to1.9 muOmega(.)cm.