高密度、长波长InGaAs量子点材料的制备与表征

Growth and Characterization of InGaAs Quantum Dots with High Density and Long Emission Wavelength

利用MOCVD外延生长技术,对InAs/GaAs量子点材料的生长参数进行调节,获得了高密度（-5×1010cm-2）的InAs量子点.室温荧光光谱表明,覆盖厚度为5 nm的InGaAs（In组分的摩尔分数为12%）低应变层量子点材料的基态发光波长为1.346μm,光谱线宽为24 meV.研究结果表明,利用较低温度生长InAs量子点,结合较高In组分的InGaAs低应变层量子点材料可以实现发光波长红移,有效地改善材料的光学特性.

InAs quantum dots with high-density（~5×1010 cm-2） were fabricated on GaAs substrate by metal-organic chemical-vapor deposition（MOCVD）,the growth parameters were studied at room temperature,the ground state peak wavelength of photoluminescence（PL） spectra and full width at Half-Maximum（FWHM） are 1.346 μm and 24 meV,respectively,when the QDs were finally capped with 5 nm InGaAs（12% In content） strain-reducing layer（SRL）.The results of PL measurements showed that the InGaAs SRL with higher In content which was fatricated at lower growth temperature could improve the optical quality of InAs QDs with strong red-shift in the spectra.