Wavelength-multiplexed spectrometer based on silicon nanowire photodetector array

Abstract

It was recently demonstrated that by adding a filter array to photodetector array, a very compact wavelength-multiplexed spectrometer can be achieved [1], [2]. These previous efforts have had both strengths and weaknesses, however. In [1], the filter array comprised etalons with different thicknesses fabricated by a multi-step process. In [2], the filter array comprised quantum dots spotted onto the device with a pipette. Here, we study a spectrometer comprising an array of silicon nanowire (Si NW) photodetectors, formed above an array of planar photodetectors. This device would have manufacturing advantages, being based on Si technology and with all NWs defined in a single lithography step...