Multiple Micro-Cavity Laser with Benzocyclobutene/Semiconductor High Reflective Mirrors Fabricated by CH 4/H 2-Reactive Ion Etching

Multiple Micro-Cavity (MMC) lasers consisting of narrow and deep grooves buried with a Benzocyclobutene (BCB) polymer, were realized by the CH4/H2-reactive ion etching (RIE) process. A threshold current of 30 mA was obtained at 200 K for the micro-cavity length ℓ H = 5.1 µm (groove width ℓ L = 183 nm, pitch Λ = 5.3 µm, total cavity length L = 300 µm, stripe width W s = 5 µm) while also showing a stable single-wavelength operation. Room temperature operation of an MMC laser consisting of 3λ/4-BCB buried grooves (= 0.70 µm) was also obtained with a threshold current as low as 18 mA for the total cavity length of 200 µm (Λ = 20 µm, 10 elements, W s = 5 µm), and the effective reflectivity of the MMC structure was estimated to be 94%.