Title :
Buried InAlGaAs-InP waveguides: etching, overgrowth, and characterization
Author :
Kollakowski, S. ; Lemm, C. ; Strittmatter, A. ; Bottcher, E.H. ; Bimberg, D.
Author_Institution :
Inst. fur Festkorperphys., Tech. Univ. Berlin, Germany
Abstract :
We report on the fabrication and characterization of InP-buried InAlGaAs rectangular core waveguides, LP-MOCVD is used for growth of the InAlGaAs-InP material system and the regrowth of InP. Reactive ion-etching is employed for achieving smooth and precise etch profiles. An efficient procedure for preparing the surface is described that results in homogeneous epitaxial InP overgrowth by preventing re-oxidation of the air-exposed etched surface. The loss characteristics of waveguides with a core layer thickness of 450 nm and widths ranging from 3.5 to 6 μm are investigated at 1.3-μm wavelength. The propagation loss is found to increase from 3 to 10 dB/cm with decreasing core width. Scattering loss caused by residual sidewall roughness is found to be the dominant loss mechanism.
Keywords :
aluminium compounds; etching; gallium arsenide; indium compounds; light scattering; optical fabrication; optical losses; optical waveguides; rectangular waveguides; semiconductor growth; surface topography; 1.3 mum; 3.5 to 6 mum; 450 nm; InAlGaAs-InP; InAlGaAs-InP material system; InP-buried InAlGaAs rectangular core waveguide fabrication; LP-MOCVD; air-exposed etched surface; buried InAlGaAs-InP waveguides; characterization; core layer thickness; dominant loss mechanism; etching; homogeneous epitaxial InP overgrowth; loss characteristics; overgrowth; precise etch profiles; propagation loss; re-oxidation; reactive ion-etching; residual sidewall roughness; scattering loss; smooth etch profiles; Electrooptical waveguides; Indium phosphide; Optical device fabrication; Optical scattering; Optical waveguides; Photonic band gap; Propagation losses; Rectangular waveguides; Semiconductor waveguides; Sputter etching;
Journal_Title :
Photonics Technology Letters, IEEE
