Spur-Less Interdigital Metal-Insulator-Metal Capacitor

A wideband interdigital metal-insulator-metal (MIM) capacitor is created and built in a two-layer low temperature co-fired ceramic (LTCC) substrate. To reduce the number of stopbands and eliminate unexpected spurs which restrict the bandwidth, short-interconnection that interconnects the open ends of interval fingers is proposed. The increment of bandwidth and capacitance of the proposed interdigital MIM capacitor is 206% and 25%, respectively. The proposed interdigital capacitor has a wider frequency applicational range and a compact size of only 8.2 x 6.2 mm. Performance discussion and comparisons are also carried out.