For Indonesia, which is located on the equator, solar energy is an alternative renewable energy source that is very promising in fulfilling the needs of the non-pollutant energy. Therefore the development of solar energy utilization must be done both in the form of research in the laboratory and its application in the form of electric energy conversion technology that can be directly utilized by our society. However, the facts show that the utilization of the energy has not been carried out optimally. Most people take advantage of new solar energy to the extent of its natural benefits, not even a few of the people are of the view that solar energy is less useful, tending to harm their lives because they have to use protectors to protect from the solar heat. For that we need enlightenment to the public about the importance of electricity through solar power. As stated by Prof. Dr. Ariswan, M.Sc., D.E.A. in his inaugural speech as Professor in Material Physics at the Faculty of Mathematics and Natural Sciences, Universitas Negeri Yogyakarta. The speech entitled "Material Engineering of Solar Cell Semiconductors to Increase Electric Energy Production towards National Energy Independence" was read before an open meeting of the Senate in the Main Meeting Room of the Rector of UNY, Saturday (12/28). Ariswan is the 148th professor of UNY.
The man who was born in Kulonprogo, 14 September 1959, said that the increase in electricity production can be set through the engineering of Chalcogenide-based semiconductor material as the main material of solar cells. The intended engineering is structural engineering and the optical properties of the material so as to produce maximum theoretical conversion efficiency, and even through engineering preparation systems with modern equipment capable of producing material systems with the ability to convert solar energy into electrical energy with conversion efficiency exceeding the maximum theoretical conversion efficiency. Semiconductor materials become materials that can be applied very quickly in the era of modern technology at this time. This material is special because at temperatures above 0 K it turns into a condenser with a relatively small forbidden bandwidth Eg, which is smaller than 3 eV. Because of the properties that this material is the basic material for active components in electronic devices such as diodes, transistors, integrated circuits and conversion technology devices such as Solar Cells. Semiconductor technology which was originally based only on silicon and germanium materials now semiconductor materials are diverse variety with physical properties that are increasingly in accordance with the needs of modern human life.
The Doctor of Physique du Materiaux Electronique Universite de Montpellier 2 France explained, the engineering of semiconductor materials is related to efforts to increase the efficiency of solar cell conversion, namely the ability of solar cells to convert solar energy into electrical energy. This increase is largely determined by two things. First, the connection quality of two P-N type semiconductors and secondly, how the ability of two or more connection arrangement materials can absorb the solar energy that is exposed at the connection.
The development of renewable energy technologies that are sustainable for the long term in large numbers through the development of material engineering must continue. "Material engineering is able to increase the efficiency of solar cell conversion by converting most of the solar energy directly into electrical energy," Ariswan said. It becomes a necessity because through research it has been known that the engineering of semiconductor materials can determine how wide the energy gap or the bandgap of a solar cell material is closely related to the ability to absorb solar energy which is then directly converted into electrical energy. When the exact wavelength spectrum of solar rays is known, material engineering can be done so that the material is able to absorb most of the solar energy which is then converted into electrical energy. The principle of engineering a tandem system as a third generation solar cell becomes a solution to increase the efficiency of solar cell conversion. Semiconductor material engineering models must continue to be studied so that the utilization of solar energy which is very abundant in Indonesia can be optimized towards national energy independence. (Dedy; Tj.Lak)
