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Structural and compositional dependence of the CdTexSe1-x alloy layer photoactivity in CdTe-based solar cells.

ABSTRACT: The published external quantum efficiency data of the world-record CdTe solar cell suggests that the device uses bandgap engineering, most likely with a CdTexSe1-x alloy layer to increase the short-circuit current and overall device efficiency. Here atom probe tomography, transmission electron microscopy and electron beam-induced current are used to clarify the dependence of Se content on the photoactive properties of CdTexSe1-x alloy layers in bandgap-graded CdTe solar cells. Four solar cells were prepared with 50, 100, 200 and 400?nm-thick CdSe layers to reveal the formation, growth, composition, structure and photoactivity of the CdTexSe1-x alloy with respect to the degree of Se diffusion. The results show that the CdTexSe1-x layer photoactivity is highly dependent on the crystalline structure of the alloy (zincblende versus wurtzite), which is also dependent on the Se and Te concentrations.

SUBMITTER: Poplawsky JD

PROVIDER: S-EPMC4974465 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Structural and compositional dependence of the CdTexSe1-x alloy layer photoactivity in CdTe-based solar cells.

Poplawsky Jonathan D JD Guo Wei W Paudel Naba N Ng Amy A More Karren K Leonard Donovan D Yan Yanfa Y

Nature communications 20160727

The published external quantum efficiency data of the world-record CdTe solar cell suggests that the device uses bandgap engineering, most likely with a CdTexSe1-x alloy layer to increase the short-circuit current and overall device efficiency. Here atom probe tomography, transmission electron microscopy and electron beam-induced current are used to clarify the dependence of Se content on the photoactive properties of CdTexSe1-x alloy layers in bandgap-graded CdTe solar cells. Four solar cells w ...[more]

PMID: 27460872

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