Development of Novel BT Laminate Material for Low-Loss and High Speed Transmission

Electronic materials capable of high speed transmission with ultra-low-loss are strongly desired in the semiconductor market. So novel BT (Bis-Maleimide Triazine) material dedicating to latest high speed applications has been developed. In this work, new BT laminate material was designed to reduce transmission loss especially in high frequency range. The study consisted of three steps to reach the low loss material. Firstly, molecular structures of each BT resin component were investigated to approach to excellent electrical properties with low moisture dependence and strong adhesion to ultra-low profile (roughness) copper foils. Generally, laminate materials are requested to have stable behavior against water absorption because it often causes serious deterioration of signal transmission at high frequency. And stronger adhesion is required to make it possible to use ultra-low profile copper foils to reduce conductor loss. Secondly, screening of inorganic fillers were conducted to understand relations between some mechanical parameters and electrical properties. In this step, strong candidates were selected for the new BT material. Finally, laminates were fabricated and several evaluations were performed. The new BT laminate material showed sufficient adhesion to low profile copper foils and lower transmission loss than conventional materials. Furthermore, it was also confirmed that excellent electrical properties were maintained after long time thermal treatment at high temperature. Thus the effectiveness of the new BT laminate material for high frequency was successfully demonstrated.