Optimization of structural and growth parameters of metamorphic InGaAs/GaAs photoconverters grown by MOCVD

3rd International School and Conference on Optoelectronics, Photonics, Engineering and Nanostructures (Saint Petersburg OPEN 2016)

Rybalchenko, D.V.^1 ; Mintairov, S.A.^1 ; Shvarts, M.Z.^1 ; Kalyuzhnyy, N.A.^1

Photovoltaic Laboratory, Ioffe Institute, Saint Petersburg, Russia^1

关键词: Growth conditions;    Growth parameters;    Hetero interfaces;    Metamorphic buffer layer;    Metamorphic heterostructure;    Potential barriers;    Series resistances;    Wide band-gap material;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/741/1/012086/pdf
DOI  :  10.1088/1742-6596/741/1/012086

来源: IOP

【 摘 要 】

Metamorphic Ga0.76In0.24As heterostructures for PV converters of 1064 nm laser radiation have been grown by the MOCVD. Parameters of the GaInAs metamorphic buffer layer with a stepwise profile of In composition variation were calculated. Its epitaxial growth conditions have been optimized, which allowed improving collection of charge carriers from the n-GaInAs base region and obtaining the photo-response quantum yield of 83% at 1064 nm wavelength. It has been found that, due to discontinuity of valence bands at the In0.24Al0.76As- p/Ga0.76In0.24As-p heterointerface (window/emitter) a potential barrier for holes arises as a result of low carrier concentration in the wide-band-gap material. The use of InAlGaAs solid solution with Al concentration of