It is demonstrated that luminescent porous silicon (PS) is applicable
to a vertical optical cavity which operates at wavelengths in the visi
ble region. The PS device consists of a high-reflectivity thin Ag film
, a light-emitting PS layer, and a quarter-wavelength multilayer refle
ctor fabricated by precisely controlled PS superlattice (PSSL) technol
ogy. The reflectivity of a prepared PSSL mirror is higher than 90% at
designed wavelengths. When excited by a UV laser, the device acts as a
Fabry-Perot resonator. Based on experimental studies of emission spec
tra as a function of major design parameters (the number of PSSL pairs
and the cavity length), the linewidth is significantly decreased to 6
meV in full width at half-maximum. The change in the linewidth with t
he cavity length is consistent with the behavior expected from a simpl
ified theoretical analysis. These results confirm that PS is applicabl
e for silicon-based photonic devices.