Research On Theantiguide Vertical Cavity Surface Emitting Lasers

Due to low threshold, narrow divergence angle, low power consumption, highmodulation bandwidth, low cost and easy for2D integration, vertical cavity surfaceemitting lasers (VCSELs) play a very important role in free-space opticalinterconnects, optical communications, optical information processing and high-speedparallel network applications, so that research institutions of domestic and foreignpaid more and more attention to it. High power and a single fundamental mode outputare required for applications of high-quality optical communications and laser printing.While conventional oxide-confined VCSELs single fundamental mode optical outputpower are less than5mW with a limited oxide aperture of4μm. High optical outputpower requires a larger oxide aperture, but single fundamental output needed a smalloxide aperture. Contradictory requirements of them result in the optical output poweris difficult to increase.Anti-resonant reflection waveguide structure (ARROW) with large built-inmodal discrimination is one of the methods used to achieve high power single-modein VCSELs. ARROW structure is formed by using insert spacer layer in the epitaxialstructure and wet etching as well as secondary epitaxial growth technology, in whichhigher order modes with significantly higher radiation losses that suppression of thehigher order mode to lasing and resulting in single fundamental mode output, suchthat single fundamental mode output is obtained. Plate approximate model have beenused in designing and analyzing the ARROW structure VCSELs, which is difficult toprecisely describe the cylindrical ARROW structure for VCSELs. In this paper, aaccurate calculations model for cylindrical ARROW structure model have been usedto device design and the losses analyze, simultaneously, a3D simulation models ofARROW structure VCSEL were built by FDTD method to study the opticalcharacteristics of the ARROW VCSELs. Lithography map and fabrication processwere designed. In additionally, key technologies of device fabrication process werestudied and device sample were fabricated in the laboratory. The main contents of thisdissertation were organized as following:(1) Leakage mode in ARROW structure mode was deeply studied. Losses offundamental and first order mode were calculated under different parameters forARROW structure by cylindrical ARROW structure model.The relationship betweenthe losses and the first cladding thinness, core size, and refractive steps were analyzed.Optical field distributions in ARROW structure were calculated.(2) Optical properties of ARROW structure VCSELs were simulated by3D FDTDmethod. Transverse mode and far field characteristics at different first claddingthickness and core size were analyzed.(3) Cavity-induced ARROW structures VCSEL and fabrication process weredesigned. The key technology of device fabrication process were deeply studied andthe samples of ARROW structure VCSELs were fabricated(4) Ohmic contact after secondary epitaxy and optoelectronic performance of ARROW structure VCSELs samples were tested and analyzed. Output power,threshold current, open voltage and series resistance of ARROW structure VCSELsare80μW,1mA，1.4V，280respectively.