A clear semiconductor based on tin could improve solar power generation
Mobility is a key parameter for semiconductor performance and relates to how quickly and easily electrons can move inside a substance. Researchers have achieved the highest mobility among thin films of tin dioxide ever reported. This high mobility could allow engineers to create thin and even transparent tin dioxide semiconductors for use in next-generation LED lights, photovoltaic solar panels or touch-sensitive display technologies.
Tin and oxygen are very familiar elements, and when combined in a certain way to become tin dioxide, the material can be made into a semiconductor. Semiconductors are fundamental to most of our technology and are the basis of computer chips, solar panels and more. Since the 1960s, tin dioxide specifically has found use in industrial applications like gas sensors and transparent electrodes for solar devices. The material is effective for these things because of its high mobility. For most applications, higher is better. However, the high mobility of tin oxide only existed in large bulk crystals, until now.
"We demonstrated the highest mobility in a thin film of tin oxide ever achieved. Improved mobility not only enhances the conductivity but also the transparency of the material," said Shoichiro Nakao, a researcher from the Department of Chemistry at the University of Tokyo. "Generally, transparency and conductivity cannot coexist in a material. Typical transparent materials such as glass or plastic are insulating, whereas conducting materials like metals are opaque. Few materials exhibit transparent conductivity -- it's very interesting!"
The more transparent a semiconductor can be, the more light it can let through. Nakao and his team have made a tin oxide thin film that allows visible light and near-infrared light to pass. This is a great benefit to the power conversion efficiency of photovoltaic solar panels, but other uses could include enhanced touch-screen displays with even better accuracy and responsiveness, or more efficient LED lights.
"Our method of production was key to creating a substance with these properties. We used a highly focused laser to evaporate pellets of pure tin dioxide and deposit or grow material exactly how we wanted it," said Nakao. "Such a process allows us to explore different growth conditions as well as how to incorporate additional substances. This means we can endow tin dioxide semiconductors with high mobility and useful functionality."
Michitaka Fukumoto, Shoichiro Nakao, Kei Shigematsu, Daisuke Ogawa, Kazuo Morikawa, Yasushi Hirose, and Tetsuya Hasegawa. High mobility approaching the intrinsic limit in Ta-doped SnO2 films epitaxially grown on TiO2 (001) substrates. Scientific Reports.
Funding and support
This work was supported by JSPS KAKENHI Grant Number 15K04687 and CREST, JST.
Solid State Chemistry Laboratory - http://www.
Department of Chemistry - https:/
Graduate School of Science - https:/
Related article - https:/
Dr. Shoichiro Nakao
Department of Chemistry, The University of Tokyo,
7-3-1 Hongo, Bunkyo-ku, 113-0033 Tokyo, Japan
Mr. Rohan Mehra
Division for Strategic Public Relations, The University of Tokyo
7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654, JAPAN
About the University of Tokyo
The University of Tokyo is Japan's leading university and one of the world's top research universities. The vast research output of some 6,000 researchers is published in the world's top journals across the arts and sciences. Our vibrant student body of around 15,000 undergraduate and 15,000 graduate students includes over 4,000 international students. Find out more at http://www.
Shoichiro Nakao | EurekAlert!
Efficient, Economical and Aesthetic: Researchers Build Electrodes from Leaves
03.07.2020 | Leibniz-Institut für Photonische Technologien e. V.
Electrons in the fast lane
03.07.2020 | Max-Planck-Institut für Polymerforschung
Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.
Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....
Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.
Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...
A promising operating mode for the plasma of a future power plant has been developed at the ASDEX Upgrade fusion device at Max Planck Institute for Plasma...
Live event – July 1, 2020 - 11:00 to 11:45 (CET)
"Automation in Aerospace Industry @ Fraunhofer IFAM"
The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM l Stade is presenting its forward-looking R&D portfolio for the first time at...
With an X-ray experiment at the European Synchrotron ESRF in Grenoble (France), Empa researchers were able to demonstrate how well their real-time acoustic monitoring of laser weld seams works. With almost 90 percent reliability, they detected the formation of unwanted pores that impair the quality of weld seams. Thanks to a special evaluation method based on artificial intelligence (AI), the detection process is completed in just 70 milliseconds.
Laser welding is a process suitable for joining metals and thermoplastics. It has become particularly well established in highly automated production, for...
02.07.2020 | Event News
19.05.2020 | Event News
07.04.2020 | Event News
03.07.2020 | Life Sciences
03.07.2020 | Studies and Analyses
03.07.2020 | Power and Electrical Engineering