More power from less silicon

A professor at

claims his latest project could boost the performance of solar cells by 40 to 50 per cent while reducing the amount of silicon used.

Vikram Dalal, the director of Iowa State’s Microelectronics Research Center, is working with PowerFilm, a manufacturer of thin, flexible solar panels, to improve the performance and stability of the company’s solar cells.

One of the challenges facing solar cell manufacturers is the fact that most cells are manufactured with crystalline silicon, the same material that is used to make semiconductors. Because computer parts have so much more value than solar cells, Dalal said there is a shortage of silicon for solar cells.

There is a way to manufacture solar cells using a lot less silicon. Dalal said non-crystalline silicon wafers that are about 2 micrometers thick can replace crystalline wafers that are about 300 micrometers thick. The result is thin solar cells that can absorb a great deal of light and can be mounted on flexible plastic and other materials.

However, the thin cells produce about half the electricity as crystalline silicon and their performance drops by about another 15 to 20 per cent over time.

Iowa State researchers have made discoveries in materials science and plasma chemistry that can improve hydrogen bonding to the silicon in the thin solar cells and could help counter this effect. Dalal said that could improve the performance of the cells by about 35 per cent and eliminate about 15 per cent of the drop in performance.