Solid oxide fuel cell (SOFC) technology has advanced significantly in the recent years, and now is an interest of many renewable energy-related industries to invest. However, the main issue of SOFC is the high operating temperature that negatively influence its performance. To reduce the temperature, a method of using bilayer electrolyte is proposed. In this study, a bilayer electrolyte of Yttria-Stabilised Zirconia (YSZ) and Scandia-Stabilized Zirconia (ScSZ) is used with the objective to reduce the temperature of SOFC to intermediate temperature ranges. To achieve the objective, bilayer YSZ/ScSZ electrolyte has been fabricated at different compositions using cold-pressing method. The pellets were sintered at three different temperature of 1350°C, 1450°C and 1550°C. In this studies, all the prepared pellets were characterized under Scanning Electron Microscopy (SEM) to examine its microstructure, Archimedes Method to measure the density and Electochemical Impedance Spectroscopy (EIS) to measure the conductivity. The results show that all of produced pellets are dense and ionic conductivity showed a rising trend as sintering temperature increases. Based on this study, the best composition is the pellet with combination of 25% YSZ: 75% ScSZ sintered at 1450°C.

Purpose Lead frame tape is a crucial support for lead frames in the IC assembly process. The tape residue on the quad flat non-leaded (QFN) could result in low reliability and failure in electrical conductivity tests. The tape residue would affect overall performance of the chips and contribute to low pass yield. The purpose of this paper is to present an in-depth study of tape residue and factors that may affect it. Design/methodology/approach An experiment using lead frame and tapes from three manufacturers with two types of die bond adhesives, namely, die attach film (DAF) and wafer back coating (WBC), was conducted. Copper (Cu) wire bonding and die bonding performances were measured in terms of process capability, stitch bond strength and die attach strength. Findings Results showed that no tape residue was observed on the thermoplastic adhesive-based lead frames manufactured by Hitachi after the de-taping process because of the tape’s thermoplastic adhesive properties. Originality/value This paper studies the occurrence of tape residue and a viable solution for it through the correct process optimization and combination of semiconductor manufacturing materials. Factors that may affect tape residue have also been studied and further research can be done to explore other options in the future as an alternate solution.