Kuk, Seungkuk Wang, Zhen Jia, Zian Zhang, Tao Park, Jong-Keuk Kim, Won Mok Wang, Lifeng Jeong, Jeung-hyun Hwang, David J. 2024-01-19T19:33:58Z 2024-01-19T19:33:58Z 2021-09-02 2019-07 2574-0962 https://pubs.kist.re.kr/handle/201004/119814 The Cu(In,Ga)Se-2 (CIGS) thin film solar cell is a promising material architecture considering its high photovoltaic (PV) efficiency at low material cost. Recently, the authors demonstrated all laser based mini-module fabrication on a transparent conducting oxide (TCO) based CIGS architecture, using a cost-effective nanosecond laser beam illuminated from the transparent glass substrate side. While indium tin oxide (ITO) is a promising TCO to this end, allowing ohmic contact with CIGS and low sheet resistance, it suffers from unwanted damage upon laser scribing based on its preferred thickness of similar to 200 nm. Therefore, in this study, we investigate the effect of laser beam size and shape on ITO damage during P2 laser scribing. Although use of an enlarged laser spot could mitigate the damage issue, larger scribing width increased the dead zone. Thus, we have implemented the elliptical laser beam shaping technology so that a longer beam axis can suppress the ITO damage also maintaining high scribing speed while a shorter beam axis dictates narrow scribing width. Based on theoretical and numerical analyses, the ITO damage free scribing trend by enlarged laser beam, at least along one laser beam axis, is attributed to the buckling mechanism that facilitates film failure by enlarged laser beam. Transient thermo-mechanical modeling results imply that larger laser beam induced thermal stress will reach the film failure threshold earlier within laser pulse duration at lower interfacial temperature. However, further time-resolved experimental investigations are necessary to find the exact film delamination timing in conjunction with possible contribution of a microexplosion mechanism. English AMER CHEMICAL SOC CONDUCTING OXIDE BACK Effect of Nanosecond Laser Beam Shaping on Cu(In,Ga)Se-2 Thin Film Solar Cell Scribing Article 10.1021/acsaem.9b00717 1 ACS APPLIED ENERGY MATERIALS, v.2, no.7, pp.5057 - 5065 ACS APPLIED ENERGY MATERIALS 2 7 5057 5065 scie scopus 000477074700054 2-s2.0-85070554532 Chemistry, Physical Energy & Fuels Materials Science, Multidisciplinary Chemistry Energy & Fuels Materials Science Article CONDUCTING OXIDE BACK CIGS thin film solar cell laser scribing thin film scribing nanosecond laser elliptical beam shaping