Silicon-based and suspended-membrane-type guided-mode resonance filters with a spectrum-modifying layer design.
The concept of a spectrum-modifying layer is proposed for the design of a silicon-based guided-mode resonance filter. To realize such a novel device, a grating and waveguide structures are fabricated simultaneously in a suspended silicon nitride membrane. The cladding layer of the silicon substrate is replaced by the silicon dioxide membrane to reduce the absorption loss of the bulky substrate. Moreover, the silicon dioxide membrane plays a role in modifying the spectral response. According to the experimental results of the proposed structures, symmetrical line shapes and improved sidebands of nonresonance are demonstrated.