Vertically-aligned nano-scale integrated inductors

We demonstrate a novel method to realize ultra-miniaturized on-chip vertical inductors for use in microwave and millimeter-wave devices. The inductor consists of a thin film of closely-packed, vertically aligned nickel nano-posts. The film is fabricated using a glancing angle physical vapor deposition method, which is CMOS compatible. The resulting nanostructured inductors were measured from 10 GHz to 70 GHz and were found to have inductances of 0.1 nH, resulting in 6pH μιη"², 60 times larger than previously reported planar inductors. A quality factor of 3 is measured and the results indicate that it continues to improve above 70 GHz, while inductance remains constant. Such nanostructured posts could potentially lead to ultra-small, ultra-wideband inductors to preserve space in integrated circuits.