A Review of Nonmultilayer Planar Crossovers: Device for Transmission and Isolation of Multiple Signals in a Planar Configuration

With the rapid development of semiconductor manufacturing technology and the booming demand in the electronics market, researchers, guided by Moore’s Law, are working toward the miniaturization and integration of devices: loading more circuits onto smaller semiconductor die and expecting smaller units to achieve superior performance. Therefore, the complexity of the transmission line routing between components or between units is rising, with iterative advanced packaging technology improving the interconnection density in integrated circuits (ICs). As a result, multiple signals in a microwave circuits inevitably intersect at one point, and the crossover comes into being.