Materials aspects of CdTe/CdS solar cells

Durose, K.; Edwards, P. R.; Halliday, D.P.

doi:10.1016/s0022-0248(98)00962-2

Cited by 211 publications

(125 citation statements)

References 35 publications

Supporting

Mentioning

121

Contrasting

Unclassified

Order By: Relevance

“…Depending on the studies carried out, various changes such as (a) re-crystallisation and grain growth, (b) interactions at CdS/CdTe interface, (c) enhancement of lifetime of charge carriers, (d) passivation of grain boundaries and (e) enhancement of device efficiencies are reported in the literature [4,52].…”

Section: Summary Of Reported Results On Cdcl 2 Treatmentmentioning

confidence: 99%

Unravelling complex nature of CdS/CdTe based thin film solar cells

Dharmadasa

Ojo

2017

J Mater Sci: Mater Electron

View full text Add to dashboard Cite

and high-temperature growth techniques. The wide bandgap (E g = 2.42 eV) window material, CdS was mainly grown by chemical bath deposition (CBD) and narrow bandgap (E g = 1.45 eV) absorber material, CdTe was grown by over 14 different methods [1]. High efficiencies were achieved by the combination of CdS with CdTe layers grown by high temperature growth methods such as closed space sublimation (CSS) or close spaced vapour transport (CSVT) for a long period. Depending on the growth technique, material growth mechanisms, micro-structure and impurity inclusions are going to vary. Although there are a large number of publications reporting material characterisation, deep understanding is required on material issues such as defects and doping concentrations.The next area needing deeper understanding is the postgrowth chemical and heat treatment. The devices fabricated using as-made CdTe materials show poor device performance in the range ~(0-6)% depending on the growth technique used. However, from 1976 [2], the researchers were aware of the drastic improvement of the device performance after heat treatment around 450 °C in air, in the presence of CdCl 2 . This was known as "CdCl 2 treatment" and device efficiencies improved to mid-teens achieving good solar cell performance. Although there were tremendous efforts to explore the complexity of changes during this treatment, full understanding has not yet been achieved.The third main area of complexity comes from the CdTe/electrical back contact formation. It is essential to clean the CdTe surface after CdCl 2 treatment, and researchers were using different chemicals to clean the surface prior to metallisation. Various electrical contacts have been used to complete the devices and varying results have been reported in the literature [3]. Initial high efficiency, reproducibility and yield, stability and lifetime are main features of fully fabricated devices to establish. Some of these Abstract Thin film solar cells based on CdS/CdTe hetero-structure has shown a drastic improvement changing from 16.5 to 22.1% efficiency during a short period of time from ~2013 to ~2016. This has happened in the industrial environment and the open research in this field has stagnated over a period of two decades prior to ~2013. Most of the issues of this hetero-structure were not clear to the photovoltaic (PV) community and research efforts should be directed to unravel its complex nature. Issues related to materials, post-growth treatment, chemical etching prior to metallisation and associated device physics are the main areas needing deeper understanding in order to further develop this device. After a comprehensive research programme in both academia and in industry on these materials, surfaces and interfaces and fully fabricated devices over a period of over three decades by the main author, the current knowledge as understood today, on all above mentioned complex issues are presented in this paper. Full understanding of this structure will enable PV developers to further improve the ...

show abstract

Section: Summary Of Reported Results On Cdcl 2 Treatmentmentioning

confidence: 99%

Unravelling complex nature of CdS/CdTe based thin film solar cells

Dharmadasa

Ojo

2017

J Mater Sci: Mater Electron

View full text Add to dashboard Cite

show abstract

“…[1][2][3] The thinfilms have a grain size of only a few micrometer, so that grain boundaries limit charge collection, and hence overall efficiency, of the solar cell. Indeed in CdTe solar cells a CdCl 2 activation step, which passivates the grain boundaries, is used to improve the efficiency by nearly an order of magnitude.…”

mentioning

confidence: 99%

“…Indeed in CdTe solar cells a CdCl 2 activation step, which passivates the grain boundaries, is used to improve the efficiency by nearly an order of magnitude. 2,3 It is therefore important to understand how an individual grain boundary affects photovoltaic performance, and characterize its dependence on doping level and illumination intensity, two parameters that affect the grain boundary barrier height. 4,5 At the grain boundary region elastic strain fields, dangling bonds and any segregated atoms give rise to electronic states within the band gap which, depending on the relative capture cross-sections for electrons and holes, can act as trap or recombination sites.…”

mentioning

confidence: 99%

A contactless method for measuring the recombination velocity of an individual grain boundary in thin-film photovoltaics

Mendis

Bowen

Jiang

2010

Applied Physics Letters

View full text Add to dashboard Cite

Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details.

show abstract

“…This is however not to be confused with the well-known behaviour of CdTe at low temperature (i.e. liquid nitrogen/helium cooled), where enhanced donor acceptor pair recombination is observed at the grain boundaries [10,[33][34]. P o is the power lost to backscattered electrons and nonradiative recombination at a free surface and/or grain boundary.…”

Section: Sem-cl Resultsmentioning

confidence: 95%

The role of transition radiation in cathodoluminescence imaging and spectroscopy of thin-foils

Mendis

Howkins

Stowe³

et al. 2016

Ultramicroscopy

Self Cite

View full text Add to dashboard Cite

Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details.

show abstract

Materials aspects of CdTe/CdS solar cells

Cited by 211 publications

References 35 publications

Unravelling complex nature of CdS/CdTe based thin film solar cells

Unravelling complex nature of CdS/CdTe based thin film solar cells

A contactless method for measuring the recombination velocity of an individual grain boundary in thin-film photovoltaics

The role of transition radiation in cathodoluminescence imaging and spectroscopy of thin-foils

Contact Info

Product

Resources

About