Effects of Ga contents on properties of CIGS thin films and solar cells fabricated by co-evaporation technique

Sunghun Jung, SeJin Ahn, Jae Ho Yun, Jihye Gwak, Donghwan Kim, Kyunghoon Yoon

Research output: Contribution to journalArticle

135 Citations (Scopus)

Abstract

This study examined the effects of Ga content in the CIGS absorber layer on the properties of the corresponding thin films and solar cells fabricated using a co-evaporation technique. The grain size of CIGS films decreased with increasing Ga content presumably because Ga diffusion during the 2nd stage of the co-evaporation process is more difficult than In diffusion. The main XRD peaks showed a noticeable shift to higher diffraction angles with increasing Ga content, which was attributed to Ga atoms substituting for In atoms in the chalcopyrite structure. Band gap energy and the net carrier concentration of CIGS films increased with Ga/(In + Ga) ratios. Regarding the solar cell parameters, the short circuit current density (J SC) decreased linearly with Ga/(In + Ga) ratios due to the lack of absorption in the long-wavelength portion of the spectrum, while the open circuit voltage (V OC) increase with those. However, V OC values at high Ga/(In + Ga) regions (>0.35) was far below than those extrapolated from the low Ga contents regions, finally resulting in an optimum Ga/(In + Ga) ratio of 0.28 where the solar cell showed the highest efficiency of 15.56% with V OC, J SC and FF of 0.625 V, 35.03 mA cm -2 and 0.71, respectively.

Original languageEnglish
Pages (from-to)990-996
Number of pages7
JournalCurrent Applied Physics
Volume10
Issue number4
DOIs
Publication statusPublished - 2010 Jul 1

Fingerprint

Solar cells
Evaporation
solar cells
evaporation
Thin films
thin films
cells
Atoms
Open circuit voltage
Short circuit currents
Carrier concentration
Energy gap
Current density
short circuit currents
Diffraction
open circuit voltage
atoms
Wavelength
absorbers
grain size

Keywords

  • Co-evaporation
  • CuInGaSe
  • Ga ratio
  • Solar cell
  • Thin film

ASJC Scopus subject areas

  • Materials Science(all)
  • Physics and Astronomy(all)

Cite this

Effects of Ga contents on properties of CIGS thin films and solar cells fabricated by co-evaporation technique. / Jung, Sunghun; Ahn, SeJin; Yun, Jae Ho; Gwak, Jihye; Kim, Donghwan; Yoon, Kyunghoon.

In: Current Applied Physics, Vol. 10, No. 4, 01.07.2010, p. 990-996.

Research output: Contribution to journalArticle

Jung, Sunghun ; Ahn, SeJin ; Yun, Jae Ho ; Gwak, Jihye ; Kim, Donghwan ; Yoon, Kyunghoon. / Effects of Ga contents on properties of CIGS thin films and solar cells fabricated by co-evaporation technique. In: Current Applied Physics. 2010 ; Vol. 10, No. 4. pp. 990-996.
@article{6258a61674094b8abe6572845be63009,
title = "Effects of Ga contents on properties of CIGS thin films and solar cells fabricated by co-evaporation technique",
abstract = "This study examined the effects of Ga content in the CIGS absorber layer on the properties of the corresponding thin films and solar cells fabricated using a co-evaporation technique. The grain size of CIGS films decreased with increasing Ga content presumably because Ga diffusion during the 2nd stage of the co-evaporation process is more difficult than In diffusion. The main XRD peaks showed a noticeable shift to higher diffraction angles with increasing Ga content, which was attributed to Ga atoms substituting for In atoms in the chalcopyrite structure. Band gap energy and the net carrier concentration of CIGS films increased with Ga/(In + Ga) ratios. Regarding the solar cell parameters, the short circuit current density (J SC) decreased linearly with Ga/(In + Ga) ratios due to the lack of absorption in the long-wavelength portion of the spectrum, while the open circuit voltage (V OC) increase with those. However, V OC values at high Ga/(In + Ga) regions (>0.35) was far below than those extrapolated from the low Ga contents regions, finally resulting in an optimum Ga/(In + Ga) ratio of 0.28 where the solar cell showed the highest efficiency of 15.56{\%} with V OC, J SC and FF of 0.625 V, 35.03 mA cm -2 and 0.71, respectively.",
keywords = "Co-evaporation, CuInGaSe, Ga ratio, Solar cell, Thin film",
author = "Sunghun Jung and SeJin Ahn and Yun, {Jae Ho} and Jihye Gwak and Donghwan Kim and Kyunghoon Yoon",
year = "2010",
month = "7",
day = "1",
doi = "10.1016/j.cap.2009.11.082",
language = "English",
volume = "10",
pages = "990--996",
journal = "Current Applied Physics",
issn = "1567-1739",
publisher = "Elsevier",
number = "4",

}

TY - JOUR

T1 - Effects of Ga contents on properties of CIGS thin films and solar cells fabricated by co-evaporation technique

AU - Jung, Sunghun

AU - Ahn, SeJin

AU - Yun, Jae Ho

AU - Gwak, Jihye

AU - Kim, Donghwan

AU - Yoon, Kyunghoon

PY - 2010/7/1

Y1 - 2010/7/1

N2 - This study examined the effects of Ga content in the CIGS absorber layer on the properties of the corresponding thin films and solar cells fabricated using a co-evaporation technique. The grain size of CIGS films decreased with increasing Ga content presumably because Ga diffusion during the 2nd stage of the co-evaporation process is more difficult than In diffusion. The main XRD peaks showed a noticeable shift to higher diffraction angles with increasing Ga content, which was attributed to Ga atoms substituting for In atoms in the chalcopyrite structure. Band gap energy and the net carrier concentration of CIGS films increased with Ga/(In + Ga) ratios. Regarding the solar cell parameters, the short circuit current density (J SC) decreased linearly with Ga/(In + Ga) ratios due to the lack of absorption in the long-wavelength portion of the spectrum, while the open circuit voltage (V OC) increase with those. However, V OC values at high Ga/(In + Ga) regions (>0.35) was far below than those extrapolated from the low Ga contents regions, finally resulting in an optimum Ga/(In + Ga) ratio of 0.28 where the solar cell showed the highest efficiency of 15.56% with V OC, J SC and FF of 0.625 V, 35.03 mA cm -2 and 0.71, respectively.

AB - This study examined the effects of Ga content in the CIGS absorber layer on the properties of the corresponding thin films and solar cells fabricated using a co-evaporation technique. The grain size of CIGS films decreased with increasing Ga content presumably because Ga diffusion during the 2nd stage of the co-evaporation process is more difficult than In diffusion. The main XRD peaks showed a noticeable shift to higher diffraction angles with increasing Ga content, which was attributed to Ga atoms substituting for In atoms in the chalcopyrite structure. Band gap energy and the net carrier concentration of CIGS films increased with Ga/(In + Ga) ratios. Regarding the solar cell parameters, the short circuit current density (J SC) decreased linearly with Ga/(In + Ga) ratios due to the lack of absorption in the long-wavelength portion of the spectrum, while the open circuit voltage (V OC) increase with those. However, V OC values at high Ga/(In + Ga) regions (>0.35) was far below than those extrapolated from the low Ga contents regions, finally resulting in an optimum Ga/(In + Ga) ratio of 0.28 where the solar cell showed the highest efficiency of 15.56% with V OC, J SC and FF of 0.625 V, 35.03 mA cm -2 and 0.71, respectively.

KW - Co-evaporation

KW - CuInGaSe

KW - Ga ratio

KW - Solar cell

KW - Thin film

UR - http://www.scopus.com/inward/record.url?scp=77951621560&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77951621560&partnerID=8YFLogxK

U2 - 10.1016/j.cap.2009.11.082

DO - 10.1016/j.cap.2009.11.082

M3 - Article

VL - 10

SP - 990

EP - 996

JO - Current Applied Physics

JF - Current Applied Physics

SN - 1567-1739

IS - 4

ER -