Electrical properties of N-type CdS and P-type CdTe thin films in CdS/CdTe solar cells

In CdS/CdTe solar cells, chemical interdiffusion at the interface gives rise to the formation of an interlayer of the ternary compoundCdSxCdTe1-x. In this work, we evaluate the effects of this interlayer in CdS/CdTe photovoltaic cells in order to improve theoretical results describing experimentalC-V(capacitance versus voltage) characteristics. We extended our previous theoretical methodology developed on the basis of three cardinal equations (Castillo-Alvarado et al., 2010). The present results provide a better fit to experimental data obtained from CdS/CdTe solar cells grown in our laboratory by the chemical bath deposition (for CdS film) and the close-spaced vapor transport (for CdTe film) techniques.

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Electrical properties and surface morphology of electron beam evaporated p-type silicon thin films on polyethylene terephthalate for solar cells applications

10.1063/1.4915164 ◽

2015 ◽

Cited By ~ 1

Author(s):

P. C. Ang ◽

K. Ibrahim ◽

M. Z. Pakhuruddin

Keyword(s):

Thin Films ◽

Electron Beam ◽

Solar Cells ◽

Electrical Properties ◽

Surface Morphology ◽

Polyethylene Terephthalate ◽

Type Silicon ◽

Silicon Thin Films ◽

P Type

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Properties of Arsenic–Doped ZnTe Thin Films as a Back Contact for CdTe Solar Cells

Materials ◽

10.3390/ma12223706 ◽

2019 ◽

Vol 12 (22) ◽

pp. 3706 ◽

Cited By ~ 1

Author(s):

Ochai Oklobia ◽

Giray Kartopu ◽

Stuart J. C. Irvine

Keyword(s):

Thin Films ◽

Solar Cells ◽

Open Circuit ◽

Activation Process ◽

Back Contact ◽

Contact Activation ◽

Doping Density ◽

Cdte Solar Cells ◽

Absorber Doping ◽

P Type

As-doped polycrystalline ZnTe layers grown by metalorganic chemical vapor deposition (MOCVD) have been investigated as a back contact for CdTe solar cells. While undoped ZnTe films were essentially insulating, the doped layers showed significant rise in conductivity with increasing As concentration. High p-type carrier densities up 4.5 × 1018 cm−3 was measured by the Hall-effect in heavily doped ZnTe:As films, displaying electrical properties comparable to epitaxial ZnTe single crystalline thin films in the literature. Device incorporation with as-deposited ZnTe:As yielded lower photovoltaic (PV) performance compared to reference devices, due to losses in the open-circuit potential (VOC) and fill factor (FF) related to reducing p-type doping density (NA) in the absorber layer. Some minor recovery observed in absorber doping following a Cl-free post–ZnTe:As deposition anneal in hydrogen at 420 °C contributed to a slight improvement in VOC and NA, highlighting the significance of back contact activation. A mild CdCl2 activation process on the ZnTe:As back contact layer via a sacrificial CdS cap layer has been assessed to suppress Zn losses, which occur in the case of standard CdCl2 anneal treatments (CHT) via formation of volatile ZnCl2. The CdS sacrificial cap was effective in minimising the Zn loss. Compared to untreated and non-capped, mild CHT processed ZnTe:As back contacted devices, mild CHT with a CdS barrier showed the highest recovery in absorber doping and an ~10 mV gain in VOC, with the best cell efficiency approaching the baseline devices.

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Heterojunction CdS/CdTe solar cells based on electrodepositedp‐CdTe thin films: Fabrication and characterization

Journal of Applied Physics ◽

10.1063/1.335735 ◽

1985 ◽

Vol 58 (9) ◽

pp. 3590-3593 ◽

Cited By ~ 22

Author(s):

R. N. Bhattacharya ◽

K. Rajeshwar

Keyword(s):

Thin Films ◽

Solar Cells ◽

Cdte Solar Cells ◽

Cdte Thin Films ◽

Fabrication And Characterization

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Thin Films of p-Type CdTe Grown with Ion-Beam-Assisted Doping

MRS Proceedings ◽

10.1557/proc-128-701 ◽

1988 ◽

Vol 128 ◽

Author(s):

Paul Sharps ◽

Alan L. Fahrenbruch ◽

Adolfo Lopez-Otero ◽

Richard H. Bube

Keyword(s):

Thin Films ◽

Solar Cells ◽

Diagnostic Tool ◽

Ion Beam ◽

Epitaxial Films ◽

Cdte Films ◽

Cdte Thin Films ◽

P Type ◽

Controlled Doping

The purpose of the present work is to investigate p-CdTe thin films grown by ionassisted doping (IAD). Controlled doping in homo-epitaxial films resulting in carder densities up to 2×1017 cm-3 was obtained using P ions as the dopant. About 1.5% of the impinging P ions became electrically active in the films. Solar cells of n-CdS/p-CdTe were prepared and used as a diagnostic tool in understanding the p-CdTe films.

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Isochronal Studies of the Structural and Electrical Properties of CdTe Films

Baghdad Science Journal ◽

10.21123/bsj.8.1.134-140 ◽

2011 ◽

Vol 8 (1) ◽

pp. 134-140

Author(s):

Baghdad Science Journal

Keyword(s):

Thin Films ◽

Electrical Properties ◽

Annealing Temperature ◽

High Vacuum ◽

Cubic Phase ◽

X Ray Diffraction ◽

Structural And Electrical Properties ◽

Evaporation Technique ◽

Cdte Thin Films ◽

P Type

The paper reports the influence of annealing temperature under vacuum for one hour on the some structural and electrical properties of p-type CdTe thin films were grown at room temperature under high vacuum by using thermal evaporation technique with a mean thickness about 600nm. X-ray diffraction analysis confirms the formation of CdTe cubic phase at all annealing temperature. From investigated the electrical properties of CdTe thin films, the electrical conductivity, the majority carrier concentration, and the Hall mobility were found increase with increasing annealing temperatures.

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Effect ofIn SituThermal Annealing on Structural, Optical, and Electrical Properties of CdS/CdTe Thin Film Solar Cells Fabricated by Pulsed Laser Deposition

Advances in Condensed Matter Physics ◽

10.1155/2016/8068396 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Alaa Ayad Al-mebir ◽

Paul Harrison ◽

Ali Kadhim ◽

Guanggen Zeng ◽

Judy Wu

Keyword(s):

Thin Film ◽

Thin Films ◽

Solar Cells ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Laser Deposition ◽

Thin Film Solar Cells ◽

Cdte Thin Film ◽

Cdte Solar Cells ◽

Cdte Thin Films

Anin situthermal annealing process (iTAP) has been introduced before the commonex situcadmium chloride (CdCl2) annealing to improve crystal quality and morphology of the CdTe thin films after pulsed laser deposition of CdS/CdTe heterostructures. A strong correlation between the two annealing processes was observed, leading to a profound effect on the performance of CdS/CdTe thin film solar cells. Atomic force microscopy and Raman spectroscopy show that the iTAP in the optimal processing window produces considerable CdTe grain growth and improves the CdTe crystallinity, which results in significantly improved optoelectronic properties and quantum efficiency of the CdS/CdTe solar cells. A power conversion efficiency of up to 7.0% has been obtained on thin film CdS/CdTe solar cells of absorber thickness as small as 0.75 μm processed with the optimal iTAP at 450°C for 10–20 min. This result illustrates the importance of controlling microstructures of CdTe thin films and iTAP provides a viable approach to achieve such a control.

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Physical properties of Bi doped CdTe thin films grown by CSVT and their influence on the CdS/CdTe solar cells PV-properties

Thin Solid Films ◽

10.1016/j.tsf.2006.12.050 ◽

2007 ◽

Vol 515 (15) ◽

pp. 5819-5823 ◽

Cited By ~ 13

Author(s):

O. Vigil-Galán ◽

E. Sánchez-Meza ◽

C.M. Ruiz ◽

J. Sastré-Hernández ◽

A. Morales-Acevedo ◽

...

Keyword(s):

Thin Films ◽

Solar Cells ◽

Physical Properties ◽

Cdte Solar Cells ◽

Cdte Thin Films

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Effect of Annealing on the Properties of Antimony Telluride Thin Films and Their Applications in CdTe Solar Cells

International Journal of Photoenergy ◽

10.1155/2014/341518 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6

Author(s):

Zhouling Wang ◽

Yu Hu ◽

Wei Li ◽

Guanggen Zeng ◽

Lianghuan Feng ◽

...

Keyword(s):

Thin Films ◽

Solar Cells ◽

Contact Layer ◽

Buffer Layers ◽

Antimony Telluride ◽

X Ray ◽

Cdte Solar Cells ◽

Structural And Electrical Properties ◽

Different Temperatures ◽

P Type

Antimony telluride alloy thin films were deposited at room temperature by using the vacuum coevaporation method. The films were annealed at different temperatures in N2ambient, and then the compositional, structural, and electrical properties of antimony telluride thin films were characterized by X-ray fluorescence, X-ray diffraction, differential thermal analysis, and Hall measurements. The results indicate that single phase antimony telluride existed when the annealing temperature was higher than 488 K. All thin films exhibited p-type conductivity with high carrier concentrations. Cell performance was greatly improved when the antimony telluride thin films were used as the back contact layer for CdTe thin film solar cells. The dark current voltage and capacitance voltage measurements were performed to investigate the formation of the back contacts for the cells with or without Sb2Te3buffer layers. CdTe solar cells with the buffer layers can reduce the series resistance and eliminate the reverse junction between CdTe and metal electrodes.

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Structural Properties of CdTe Thin Films for Solar Cell Applications Deposited on Flexible Foil Substrates

MRS Proceedings ◽

10.1557/proc-1165-m08-26 ◽

2009 ◽

Vol 1165 ◽

Cited By ~ 1

Author(s):

Vasilios Palekis ◽

Deidra Ranel Hodges ◽

Don L Morel ◽

Lee Stefanakos ◽

Chris S Ferekides

Keyword(s):

Thin Film ◽

Thin Films ◽

Growth Rate ◽

Grain Size ◽

Solar Cells ◽

Solar Cell ◽

Substrate Temperature ◽

Source Temperature ◽

Cdte Solar Cells ◽

Cdte Thin Films

AbstractCadmium telluride (CdTe) is a leading thin film photovoltaic (PV) material due to its near ideal band gap of 1.45 eV and its high optical absorption coefficient. The typical CdTe thin film solar cell is of the superstrate configuration where a window layer (CdS), the absorber (CdTe), and a back contact are deposited onto a glass slide coated with a transparent electrode. Substrate CdTe solar cells where the above listed films are deposited in reverse order are not common. In this study, the growth of CdTe thin films deposited on foil substrates by the close-spaced sublimation (CSS) has been investigated for the purpose of fabricating substrate based CdTe solar cells. The CdTe films were deposited at substrate temperatures (TSUB) in the range of 300 to 600°C, and source temperatures (TSRC) in the 600 to 650°C range. The effect of the substrate-source temperature variations on the growth rate, film structure and morphology were studied using XRD and SEM. It was found that for low substrate temperature and as the growth rate increases, grain size was the same but the films appeared to be more uniform and more densely packed with less or no pinholes. The growth rate increased as the source temperature increased. The substrate temperature clearly influences the grain growth and the preferred orientation. As the substrate temperature increased the growth rate decreased and the grain size varied from 2 to 6 μm. XRD analysis showed that with the increase in substrate temperature film orientation changes from preferential along the (111) direction to a mix of (111) (220) and (311).

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