title: Characterizing microscale aluminum composite layer properties on silicon solar cells with hybrid 3D scanning force measurements.
abstract: This article presents a novel technique to estimate the mechanical properties of the aluminum composite layer on silicon solar cells by using a hybrid 3-dimensional laser scanning force measurement (3-D LSFM) system. The 3-D LSFM system measures the material properties of sub-layers constituting a solar cell. This measurement is critical for realizing high-efficient ultra-thin solar cells. The screen-printed aluminum layer, which significantly affects the bowing phenomenon, is separated from the complete solar cell by removing the silicon (Si) layer with deep reactive ion etching. An elastic modulus of ~15.1 GPa and a yield strength of ~35.0 MPa for the aluminum (Al) composite layer were obtained by the 3-D LSFM system. In experiments performed for 6-inch Si solar cells, the bowing distances decreased from 12.02 to 1.18 mm while the Si layer thicknesses increased from 90 to 190 μm. These results are in excellent agreement with the theoretical predictions for ultra-thin Si thickness (90 μm) based on the obtained Al composite layer properties.
authors.affiliation: Department of Mechanical Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.
authors.forename: Sung-Kuk
authors.initials: SK
authors.lastname: Bae
authors.affiliation: Department of Mechanical and System Design Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.
authors.forename: Beomjoon
authors.initials: B
authors.lastname: Choi
authors.affiliation: Department of Mechanical Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.|Department of Mechanical and System Design Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.
authors.forename: Haseung
authors.initials: H
authors.lastname: Chung
authors.affiliation: Department of Mechanical Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.|Department of Mechanical and System Design Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.
authors.forename: Seungwon
authors.initials: S
authors.lastname: Shin
authors.affiliation: Photovoltaic Research Center, Korea Institute of Energy Research (KIER), 152 Gajeong-ro, Yuseong-gu, Daejeon, 305-343, South Korea.
authors.forename: Hee-eun
authors.initials: HE
authors.lastname: Song
authors.affiliation: Department of Mechanical Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.|Department of Mechanical and System Design Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.|Biomedical and Nanoengineering Research Center, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, 121-791, South Korea.
authors.forename: Jung Hwan
authors.initials: JH
authors.lastname: Seo