Japan Develops New Technology for Production of Solar Cells

Japan Develops New Technology for Production of Solar Cells

Japanese researchers announced that they have for the first time in the world developed techniques for producing solar cells by coating liquid silicon to form amorphous silicon films. New technologies will help reduce the cost of thin-film solar cells.

Silicon is an important raw material for making mobile phones, liquid crystals, and solar cells. At present, solar cells are mostly made of solid and gaseous silicon materials, but the cost of processing solid and gaseous silicon materials is high and the time required is longer.

A research team headed by Shimoda University, a professor at the University of Advanced Science and Technology in Hokuriku, in 2006, produced a stable liquid silicon with a high molecular compound containing silicon and hydrogen as a solute. This time, based on a thorough study of the characteristics of liquid silicon, they have developed a new technology for manufacturing thin-film solar cells.

New technology to produce solar cells first removes impurities from liquid silicon, then drops liquid silicon onto a glass substrate in a nitrogen-filled device, and allows the substrate to spin at a high speed of about 3,000 times per minute to evenly distribute the liquid silicon. A thin layer was formed on the substrate, and finally heated at a high temperature of about 400 degrees Celsius for several tens of seconds to obtain a stable amorphous silicon thin film.

By repeating the above process three times and adding boron and phosphorus, three different layers of silicon films can be produced. After adding electrodes to produce solar cells, its power generation efficiency is about 20% of ordinary solar cells. Although the efficiency is not high, the cost is reduced by 60% to 70%.

At present, the research team is preparing to cooperate with Japanese domestic manufacturers to apply this technology to the production field as soon as possible.