Silicon microcavity based on 1-D photonic bandgap structure

Abstract

In this paper, we report on the design, modeling, fabrication, and characterization of an amorphous silicon microcavity. The microcavity is fabricated using a one-dimensional photonic bandgap structure. The structure was grown by plasma deposition method. Quarter wavelength thick stacks of hydrogenated amorphous silicon nitride and hydrogenated amorphous silicon oxide were consecutively deposited using low temperature plasma enhanced chemical vapor deposition. For the characterization of the dielectric microcavities the intrinsic photoluminescence of the amorphous silicon is used. Bulk amorphous silicon has a luminescence bandwidth of 250 nm. Due to the presence of the microcavity, the luminescence is enhanced by at least an order of magnitude at the resonance wavelength of 700 nm. Additionally, the luminescence is inhibited in the photonic bandgap occupying a spectral band of 150 nm. The microcavity resonance has a quality factor of 120 corresponding to a luminescence linewidth of 6 nm. The enhancement of the photoluminescence is understood by the modified photon density of states of the dielectric microcavity.