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 amount 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 8.2×6.2 mm. Performance discussion and comparisons are also carried out.
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