Nanogap quantum dot photodetectors with high sensitivity and bandwidth

Hegg, Michael C.; Horning, Matthew P.; Baehr-Jones, Tom; Hochberg, Michael; Lin, Lih Y.
March 2010
Applied Physics Letters;3/8/2010, Vol. 96 Issue 10, p101118
Academic Journal
We report high-performance nanoscale photodetectors utilizing annealed nanocrystal quantum dots (QDs) within a nanoscale metal electrode gap. By optimizing the nanogap size and fabrication process, the device demonstrates a significantly better sensitivity (noise equivalent power=7.76×10-14 W/Hz1/2) and bandwidth (≥125 kHz) than previously reported nanoscale photodetectors. Furthermore, by utilizing a lateral photoconduction structure and a self-assembled layer of QDs, the detector fabrication is highly compatible with many substrates and device architectures.


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