Layer-by-layer deposition of colloidal semiconductor nanocrystals for integration of infrared photon-detectors on 3D topography

This paper presents photosensitive colloidal nanocrystal films for the integration of photon-detectors on 3D topography surfaces. Silicon wafers with anisotropically etched cavities are used as substrates, and gold electrodes are patterned across the 3D surface. A layer-by-layer dip-coating method is used to deposit semi-conductive PbSe colloidal nanocrystals from solution, in order to form infrared photon-detectors on the tapered surfaces. An integrated device capable of detecting the angle of the incoming infrared illumination is implemented to demonstrate the potential of this technology.