Narrow-Linewidth and Wavelength-Tunable Red-Light Emission From an Si-Quantum-Dot Embedded Oxynitride Distributed Bragg Reflector

Wavelength-tunable narrow-linewidth red-light emission generated from Si quantum dots (Si-QDs) that are embedded in Si-rich SiO_x/SiN_x:Si-QDs distributed Bragg reflector (DBR) are demonstrated using low-temperature and low-plasma chemical vapor deposition. With increasing layer thickness Δd of the 20-pair SiOx/SiN x:Si-QD DBR structure, its narrow linewidth and high-extinction-ratio transmittance peak between central and nearby stopband serve as high-Q filter to sharpen the broadband Si-QD photoluminescence (PL) from 140 to 19 nm. By comparing the PL intensity of 667 nm for a DBR with the 20-time multiplied single-pair case, an enhancement factor of 1.86 is in good agreement with the theoretical estimation of 1.74. The transmitted PL peak wavelength λp of PL spectrum is tunable from 667 to 706 nm, as predicted by a relationship between the shifted wavelength and the refractive index of Δλ_p ≅ 2 (n_SiOx + n_SiNx) Δd. The transmitted PL response can be simulated from the luminescence summation of each light-emitting layer within the DBR structure.