Design And Growth Of InGaAsSb New Structure Quantum Well Lasers

GaSb-based quantum well the new structure of bipolar cascade laser can effectively improve the device output power,improving the device characteristics,have been attracting great attention.In this paper,high quality a(?)mony compounds GaSb-based material growth and characterization,made a more detailed study on the ultra-thin-layer epitaxial growth, quantum well structure,optimization of design has made some progress.On this basis,the new structure of the InGaAsSb bipolar cascade laser quantum well structure of the theoretical optimum design achieved the following results:Theoretical analysis of the basic properties of GaSb-based materials,using a linear interpolation method to calculate InGaAsSb,AIGaAsSb quaternary system lattice constant, band gap,refractive index,and using molecular beam epitaxy(MBE) technology on GaSb, InSb,and InGaAsSb / AIGaAsSb / GaSb multiple quantum well materials,the epitaxial growth conducted in-depth research,analysis of the growth temperature,growth rate,Ⅴ/Ⅲbeam ratio,doping and growth rate and some other important process parameters on the material characteristics.Optimized quantum well laser materials,optimum growth conditions,the use of RHEED,X-ray double crystal diffraction,optical fluorescence spectra of the material was tested and analyzed.And successfully obtained high-quality InGaAsSb / AlGaAsSb multiple quantum well structure material.Based on the investigation of experiment We discussed the main problems and limits of high power semiconductor lasers with ordinary structure,then introduced theory of the high efficiency high power bipolar cascade semiconductor lasers.We analyzed the characteristics such as:inner efficency and extemal differential quantum etal.Using the new theory,we designed InGaAsSb/AlGaAsSb bipolar cascade quantum well lasers(λ=2.0μm).to enhance the device differential quantum efficiency,lower threshold current and improve the beam quality,improve device power.