Development of low-loss broad-band planar baluns using multilayered organic thin films

This paper presents the design and development of a low-loss and wide-band width multilayered Marchand balun. The balun has been implemented using printed circuit board materials with integrated multilayered organic thin films. We have designed the top layer transmission lines on twin-thickness organic thin films to achieve low loss and wide bandwidth for the balun. The experimental results demonstrate that the balun achieves less than 0.5-0.7 dB insertion loss throughout the 4-20-GHz operation bandwidth. The phase and amplitude imbalances are less than 5° and 0.5 dB, respectively. Time-domain measurement results demonstrate that the balun has negligible dispersion.