CuAl intermetallic compound for Cu alternative

Abstract

In this paper, we report the properties and reliability of CuAl as a candidate for new interconnect materials. The tape test results for CuAl showed good adhesion to th-SiO2, and the BTS (3 MV/cm, 30 min, 250°C) test results confirmed that CuAl has high BTS reliability. In terms of resistivity, CuAl was shown to have lower resistivity than Cu including a liner/barrier layer, at less than 6 nm. No voids were observed after EM (1 MA/cm2, 275 °C, 25 h) test, whereas voids were observed in Cu/TaN. The results of this study indicate that CuAl is a promising candidate as a new interconnect material that does not require a liner/barrier layer.