Application Of GaInP Stress - Compensating Layer In InAs / GaAs Quantum Dot Preparation

Strain conpensation technology has been taken seriously as an effective methodto achieve high quality quantum dots. This thesis studies the use of GaInP straincompensation layer in InAs/GaAs quantum dot system, from both theoretical andexperimental to analysis the effect of strain compensation layer.Firstly, analysed the system’s stress distribution theoretically, the results showthat the stress distribution in space layer surface is based on the former layer’scompressive strain area. After inserted GaInP strain compensation layer, the needlessstress was compensated. With the Ga component and the thickness of compensationlayer increased, the strain energy increased, the compensation effect was enhanced atfirst and then weakened.Secondly, single layer InAs/GaAs quantum dot and GaInP material was preparedby MOCVD. The best values of growth temperature, growth time, Ⅴ/Ⅲ ratioofsingle layer quantum dot is473℃,5.5s,15respectively, the quantum dot density is5.7×1010cm-2and defect density is2.0×107cm-2, the average diameter and height ofthe dot is36nm and5.4nm respectively. For GaInP bulk material, there are twogroups samples meet the requirements of strain compensation technology, their Gacomponent is0.566and0.606, the growth temperature and Ⅴ/Ⅲ ratio are473℃,150and473℃,152, the growth rate are2.35/s and1.5/s.Thirdly, grew strain-compensated double layer quantum dot structures. Theresult showed that:1)the use of strain compensation layer can improve the quality ofquantum dot;2)different growth temperature, thickness, component of strain compen-sation layer cause different compensation effect. The optimum value for temperatureis473℃. For the thickness, the optimum value of two groups is1.175nm and1.65nmrespectively. For Ga component, the0.566group is better than the0.606group.Finally, summarized the work done, analysised the deficiencies in the study andlook into the distance.