Hybrid Bonding of Cu and Manganin by using IPA-VUV Irradiation

Because of the thermal stability of Manganin, it is considered as the promising material to utilize such as in ultra-precision measurement and low temperature environment in future automotive electronics and batteries. In order to ensure the electrical and thermal conductivity to conventional interconnection layers, a new method to bond manganin and Cu directly at low temperature was developed in this study. The VUV radiation under IPA atmosphere contributed to form the carboxylates bridging layer, which makes Cu and manganin can be bonded at 150°C and 10 MPa. The as-bonded adhesive strength can reach 250 N/m at the optimized surface treatment condition. After the high temperature humidity test, there was almost no change in the adhesive strength due to the contribution of the anti-hydrolytic carboxylates layer. To the best of our knowledge, this is the first time to bond the bulk manganin and Cu at such low temperature and pressure.