Electronic Materials Letters

, Volume 15, Issue 3, pp 314–322 | Cite as

Copper–Nickel Alloy Plating to Improve the Contact Resistivity of Metal Grid on Silicon Heterojunction Solar Cells

  • Sang Hee Lee
  • Doo Won Lee
  • Kyoung-jin Lim
  • Won-suk Shin
  • Jeong KimEmail author
Original Article - Electronics, Magnetics and Photonics


As a dominant metallization technique of crystalline silicon solar cells, screen printing with silver paste has been generally used in photovoltaic industries. In case of the silicon heterojunction solar cells (SHJ) structure, a metal contact with silver paste has lower electrical conductivity than pure silver due to the other compositions of the paste. For the reason, copper plating is attractive substitute for the silver paste since the plated-copper contacts have high conductivity and easily reduce line width which is beneficial to light absorption. In this experiment, we studied copper–nickel (Cu–Ni) alloy plating to form a seed layer of the copper plating on an indium tin oxide (ITO) layer which is used for the transparent conductive oxide of the SHJ solar cells. As a requirement of suitable seed layer, contact resistivity (ρc) between the seed and the ITO is important to obtain high fill factor by decreasing series resistance of solar cells. Contact resistivity values of the samples with varied nickel contents in the Cu–Ni films were extracted by using transfer length method. Also, the composition ratio of the alloy layer was analyzed by energy dispersive spectrometer. Moreover, X-ray diffraction was used to compare lattice parameter and crystallite size of the film.

Graphical Abstract


Silicon heterojunction solar cells Cu–Ni alloy plating Seed layer Contact resistivity Copper plating 



This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20173010012940) and by the Ministry of Trade, Industry, and Energy, Korea Evaluation Institute of Industrial Technology (KEIT) (No. 10043793).


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Copyright information

© The Korean Institute of Metals and Materials 2019

Authors and Affiliations

  • Sang Hee Lee
    • 1
  • Doo Won Lee
    • 1
  • Kyoung-jin Lim
    • 2
  • Won-suk Shin
    • 2
  • Jeong Kim
    • 1
    Email author
  1. 1.Department of Electronics Engineering, Green Strategic Energy Research InstituteSejong UniversityGwangjin-GuKorea
  2. 2.Jusung EngineeringGwangju-SiKorea

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