A novel fabrication method of micro Bragg Grating optical sensor using combination of electron beam lithography and nanoimprint technologies

In this work, a cost-efficient polymer based Bragg Grating (BG) optical sensor was successfully fabricated by NIL (nanoimprint lithography) process. The master structures for the NIL process were achieved by the combination of electron beam lithography, photolithography and dry etching techniques on an inorganic film covered silicon wafer. For the following NIL process, silicon-containing, inorganic–organic hybrid material OrmoCore® was used as the rib waveguide core material due to its low optical loss in the visible wavelength region. With the changing of the environment temperature, the grating period and the refractive index of the BG would be altered. By measuring the shift of the wavelength in the transmission spectrum, the temperature value could be simply calculated. Keywords: FBG, optical sensor, NIL