Structural Design And Epitaxial Preparation Of 1060nm Tunnel Cascaded Multi-active Region Semiconductor Laser

High-power semiconductor lasers are widely used in industrial processing,medical beauty,military and other fields due to their small size,high efficiency and long life.In recent years,systems such as laser ranging and laser welding have become more and more compact,and higher requirements have been placed on the output power,divergence angle,and operating voltage of 1060 nm semiconductor lasers.The tunnel cascaded multi-active-area semiconductor laser uses a reverse-biased tunnel junction to cascade the n lasers in-chip,achieving an internal quantum efficiency of n times,high power output at a small current,and an increase in the light-emitting area increases the COMD level of the device..In this paper,the following research is carried out on the structural design and epitaxial fabrication of 1060 nm tunnel cascaded multi-active region high power semiconductor lasers:(1)The research background of tunnel cascaded multi-active region semiconductor lasers is studied.The development history of semiconductor lasers is introduced.The traditional methods for improving the power of semiconductor lasers and improving power are analyzed.The working principle,advantages and development status of tunnel cascaded multi-active region semiconductor lasers are mainly studied.(2)The epitaxial growth technique of semiconductor lasers was studied.The development history of MOCVD epitaxial growth technology is introduced,and the composition and working principle of the EMCORE D125 LP-MOCVD system in this laboratory are highlighted.In addition,the two techniques used for epitaxial testing: photoluminescence(PL)spectrum,electrochemical(ECV)working principle are described,and the corresponding laboratory instruments are introduced.(3)The active area structure is designed and material growth is completed.Based on the 6×6 Luttinger-Kohn finite difference method,the InGaAs/GaAs quantum well structure was simulated by matlab programming.The relationship between the quantum well material composition and the well width was calculated when the transition wavelength was fixed at 1060 nm,and the quantum well structure was determined.The effects of temperature and V/III ratio on quantum wells during MOCVD growth were studied,and high-quality active region epitaxial materials were obtained.(4)A single active-area laser structure is designed and material growth is completed.The optical waveguide theory of semiconductor laser is introduced.The structure of the waveguide layer is simulated and the asymmetric large cavitywaveguide structure is designed.Then the simulation of the confinement layer was carried out and the structure of the confinement layer was designed.Finally,the effects of growth temperature and V/III ratio on Al0.1Ga0.9As/Al0.3Ga0.7As DH were studied,and high quality waveguide layer and confinement layer epitaxial materials were obtained.(5)Designed high-performance tunnel junctions and completed material growth.InGaAs QW tunnel junction and InGaAs DQW tunnel junction are designed based on GaAs homojunction.The tunnel junction device is obtained by epitaxy and process.The best performance tunnel junction InGaAs DQW tunnel junction is obtained by test comparison.(6)Material growth and device preparation of a multi-active area laser.First,a1060 nm tunnel cascaded three active-area half-laser epitaxial wafer was grown by MOCVD,and the PL spectrum and doping concentration of the epitaxial wafer were tested by PL technique and ECV technique.Then,the epitaxial wafer is prepared by using a post-process to obtain a laser single tube and a mini bar.Finally,the photoelectric characteristics of the laser are tested.The laser single-tube threshold current is 407 mA and the slope efficiency is 1.87 W / A.When the current reaches12 A,the maximum output power is 19.26 W.The mini bar threshold current is approximately 1.22 A and the slope efficiency is 1.88 W / A.When the injection current reaches 28 A,the maximum output power is 47.76 W.