Replicated arrays of hybrid elements for application in a low-cost micro-spectrometer array

We report on the fabrication and characterization of replicated hybrid elements for low-cost micro-spectrometer array applications. An array of hybrid elements, where one surface combines the fairly large dimensions of refractive microlenses with the submicron features of a diffraction grating, was successfully replicated by hot embossing. The parameters are: lens diameter = 990 mu m, height = 60 mu m, grating period = 1 mu m, linewidth = 300 nm and grating depth = 2 mu m. These replicated spectrometer elements showed a maximum resolution of 2.25 nm and a stray-light suppression better than 30 dB.