GaAsSb/InAs/(In)GaAs type II quantum dots for solar cell applications

0466021 - FZÚ 2017 US eng A - Abstract
Vyskočil, Jan - Hospodková, Alice - Zíková, Markéta - Oswald, Jiří - Pangrác, Jiří - Petříček, Otto - Hulicius, Eduard
GaAsSb/InAs/(In)GaAs type II quantum dots for solar cell applications.
ICMOVPE XVIII. Program and Exhibit Guide. Warrendale: MRS - Conference Services, 2016 - (Biefeld, R.). s. 44-44
R&D Projects: GA ČR(CZ) GP14-21285P
Institutional support: RVO:68378271
Keywords : InAs * GaAsSb * InGaAs * quantum dot * solar cells
Subject RIV: BM - Solid Matter Physics ; Magnetism

We focused on design of suitable buffer and covering layers of InAs/GaAs QD with the aim to increase the carrier extraction rate in the QD solar cell structures. Covering GaAsSb strain reducing layers (SRL) with type-II band alignment offer several advantages. They increase the QD size, type II band alignment decrease recombination rate of electrons and holes in QDs and enhance carrier extraction. The InGaAs buffer SRL bellow InAs QDs further enhanced the extraction of photogenerated carriers. For comparison the reference structure with GaAs capped InAs QDs was prepared, too. A set of samples was prepared to demonstrate the effect of electric field on photocurrent results. Properties of the structures were compared and the mechanism of carrier extraction is discussed. We showed that InGaAs buffer SRL together with increasing profile of antimony concentration in covering GaAsSb SRL can significantly improve the resulting properties of solar cell structures.
Permanent Link: http://hdl.handle.net/11104/0264476