Optical Sensor Array based Nanospectrometer: Fabrication of high resolution 3D NanoImprint master templates and bonding of Fabry-Pérot filter array onto photodetector array

In the field of optical spectroscopy, spectrometers are high resolution optical sensors that have emerged as a platform for a wide range of application fields. Commercially available spectrometers are bulky and expensive. Hence, this limits its integration into modern mobile and wearable devices. To overcome this limitation, miniaturization of spectrometers is an interesting target for a wide range of emerging applications. The most attractive concept of fabricating miniaturized spectrometers is the Fabry-Pérot filter (FP-filter) array based micro spectrometer. To enable spectral selectivity, the mian aim of a project at INA is to fabricate miniaturized spectrometer with 64 static FP-filters in an array to cover the entire visible (VIS) spectral range for sensing applications. In the production of multiple spectral FP-filter arrays, a large number of 3D FP-cavities of precise and varying vertical heights are required which is challenging to fabricate. The conventional photolithography technique is inefficient in achieving this goal as a large number of processing steps are required, which increases the processing time and fabrication cost. Therefore, this work implements a novel fabrication technology for producing miniaturized and high resolution Nanospectrometer which is the NanoImprint Lithography (NIL). It is a non-conventional patterning technique where a deformable polymer resist is mechanically molded to form 3D functional structures for a desired application.