We present copper structures composed of multilayer, stacked inductors (MLSIs) with tens of micro-Henry inductance for use\r\nin low frequency (sub 100 MHz), power converter technology. Unique to this work is the introduction of single-level lithography\r\nover the traditional two-level approach to create each inductor layer. The result is a simplified fabrication process which results in\r\na reduction in the number of lithography steps per inductor (metal) layer and a reduction in the necessary alignment precision.\r\nAdditionally, we show that this fabrication process yields strong adhesion amongst the layers, since even after a postprocess\r\nabrasion technique at the inner diameter of the inductors, no shearing occurs and connectivity is preserved. In total, three separate\r\nstructures were fabricated using the single-level lithography approach, each with a three-layered, stacked inductor design but with\r\nvaried geometries. Measured values for each of the structures were extracted, and the following results were obtained: inductance\r\nvalues of 24.74, 17.25, and 24.74 �µH, self-resonances of 9.87, 5.72, and 10.58 MHz, and peak quality factors of 2.26, 2.05, and 4.6,\r\nrespectively. These values are in good agreement with the lumped parameter model presented.
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