ICAs for automotive applications in higher temperature ranges

This paper focuses on the results of investigations on ICAs in higher temperature ranges. The wide use of electronic components in the field of automobiles requires low-cost materials and technologies. The electronic behavior of these components also has to withstand a high temperature level of 120°C to 130°C. The mechanical and electrical reliability of soldered electronic components is decreased under these temperature conditions. As one possible way to solve this problem the use of ICAs is considered for high temperatures. The investigations take into consideration different surfaces on substrates and components (e.g. NiAu, Cu, NiPd) and a representative selection of ICAs of different manufactures. One criteria of the selection is a successful passing of a printing test of a 200 μm pitch structure. The starting point of all investigations is the manufacturing of test vehicles, which were made under the use of the specific indications of the particular ICA producer. All test vehicles are stored with accelerated tests (e.g. 85°C/ 85 RH) and high temperature storage (150°C, 500 h). Additionally a special preparation of the surfaces is used. A plasma treatment step is performed before the manufacturing process. The effect is a higher activation of the contact surfaces and an improved adhesion of the ICA join. These special test vehicles are compared with test vehicles without treatment. The behavior of all investigated boards are documented by their electrical and mechanical characteristics and will be discussed and judged