□ The 'High Efficient Flexible CIGS Thin Film Solar Cells Using Polymer Substrate technology' developed by the Korea Institute of Energy Research (President Kwak Byong Sung) won the award from Ministry of Science and ICT at the award ceremony of '2019 Korea Climate Technology Exhibition' held on Wednesday, July 24. 

□ 'High Efficient Flexible CIGS Thin Film Solar Cells Using Polymer Substrate technology“ is a technology that utilizes lightweight flexible plastic substrate to secure the applicability of high stability CIGS thin film solar cell and enhance * photoelectric conversion efficiency dramatically.* Photoelectric conversion efficiency: Percentage of the ratio of incident solar energy to electric energy output from the solar cell

○ CIGS (CuIn1-xGaxSe2) compound composed of four elements of copper, indium, gallium and selenium is chemically stable with a light absorption coefficient 10 times larger than that of silicon and high durability. If this is used as a light absorbing layer, it is possible to realize high efficiency by only consuming a small amount of material and simplifying the process in manufacturing a solar cell. However, it is difficult to enter the market due to some reasons including a decline in the price of existing crystalline PV modules.

○ Dr. Jae-Ho Yoon and his researchers at the new and renewable energy research institute of KIER have developed a low-temperature film formation technology for CIGS thin films applicable to polymer substrates and succeeded in developing CIGS thin film solar cell manufacturing technology applied with *Lift-Off process based on systematic analysis technology and reliability know-how. In addition, they have achieved solar cell conversion efficiency (20.4%), which is comparable to **the highest level in the world.

* Lift-Off: Technology that can thinly coat the polymer on the glass substrate and make the substrate as thin as possible.** World's highest level: 20.8%, achieved by Swiss EMPA (photoelectric conversion efficiency of 1cm2 small area solar cell device manufactured on polyimide substrate)

○ This is next generation high value added technology which is easy to cope with demand unlike existing mass production type solar module technology for mass supply. It is suitable for various industries including building integrated solar photovoltaic (BIPV) but also for device-integrated photovoltaic (DIPV).

□ Dr. Yoon Jae-ho said, "unlike other organic-based solar cells, as high-efficiency solar cell technology is secured on lightweight plastic substrates based on CIGS thin film with high stability, we have proved the possibility to manufacture solar modules having both material stability, efficiency and functionality“ and continued to say, "it is expected that it will be a new bridgehead for the commercialization of domestic CIGS thin film solar cell that has shrunk since the withdrawal of large enterprises in the domestic market and will contribute greatly to the urban power generation project to be carried out by the Ministry of Science and ICT.

□ This research has been supported by the Ministry of Science and ICT (Climate Change Response Technology Project), and its research results are published in the well-known international journals such as ‘Advanced Energy Materials' & Interfaces', proving its excellency. In addition, it was selected as one of 2019 top ten climate technologies" for excellence created during the recent three years of research and development in the national climate change adaptation.