Keynote speech — 2: Development of thin-film CIGS solar cell technology in Malaysia

CIGS thin-film solar cell, also known as second generation PV technology, uses advanced materials in order to increase solar cell efficiency. One of the thin-film materials is Copper Indium di-Selenide (CuInSe2) or CIS. CIS was considered promising for solar cells because of its favourable electronic and optical properties. It was later found that by substituting Gallium (Ga) for Indium (In), the band-gap can be increased from about 1.04 electron-Volt (eV) for CIS films to about 1.68eV for Copper Gallium di-Selenide (CuGaSe2) or CGS cells in short. Optimal devices have been fabricated with partial substitution of Ga for In, leading to a substantial increase in overall efficiency and more optimal band-gap. These solar cells are commonly known as a copper indium gallium di-selenide [CuInxGa(1−x)Se2], or CIGS, cells. The CIGS solar cell is designed with direct band-gap material that can absorb a significant portion, from 300nm to 1300nm, of the solar spectrum. Because of this, CIGS is capable to achieve the highest efficiency of any thin-film technology. CIGS utilizes less material which allows lower power-to-weight ratio as well as reducing the cost for fabrication. A tuneable band-gap allows the possibility of tandem CIGS devices. The grain boundaries form an inherent buffer layer, preventing surface recombination and allowing for films with grain sizes of less than 1 μm to be used in device fabrication. CIGS panels have excellent performance during low light, cloudy or hazy conditions. Thus, a research on the development of thin-film CIGS solar cell technology and its charge controller module is proposed. The main objective of the research is to acquire the knowledge and the process capability of locally developed CIGS solar cell technology. This objective is also in line and facilitates the nation target to achieve 5% of renewable energy consumption by year 2020.