Select your localized edition:

Close ×

More Ways to Connect

Discover one of our 28 local entrepreneurial communities »

Be the first to know as we launch in new countries and markets around the globe.

Interested in bringing MIT Technology Review to your local market?

MIT Technology ReviewMIT Technology Review - logo


Unsupported browser: Your browser does not meet modern web standards. See how it scores »

{ action.text }

Suntech has developed a way to form monocrystalline material using a modified version of the multicrystalline process.

It uses seed crystals, but instead of being gradually drawn out of the silicon (as with the conventional monocrystalline process), they are arranged at the bottom of a crucible and completely covered with melted silicon. Then heat is extracted through the bottom of the crucible, ensuring that crystallization begins at the bottom, where the seeds are.

This is essentially the process patented decades ago. Refinements Suntech has made help overcome one of the main challenges the process presents: the molten silicon in contact with the edges of the container forms its own seeds, and as a result, the final slab of silicon is monocrystalline on the inside and multicrystalline toward the outside.

Suntech figured out how to keep the multicrystalline area to a minimum: the resulting ingot is 70 percent monocrystalline. Pure monocrystalline wafers are made from the center of the ingot. The material on the edges, which is half monocrystalline and half multicrystalline, is also used. Cells made of this turn out to be about 10 percent more efficient than ordinary multicrystalline cells, which is almost as efficient as purely monocrystalline cells.

Wenham says the process can use existing wafer-processing equipment, so it can be scaled up quickly. “The process could be quite a game-changer in photovoltaics, as it offers much higher performance at reduced costs,” he says. 

Wenham says that Suntech expects much of the industry to adopt similar technology in the next two years. Because the basic principle is no longer under patent, many companies have been able to develop their own versions of it. He says Suntech is looking to patent technologies related to using the new materials to make solar panels.

12 comments. Share your thoughts »

Credit: Suntech

Tagged: Energy, energy, renewable energy, solar, Suntech, silicon wafers

Reprints and Permissions | Send feedback to the editor

From the Archives


Introducing MIT Technology Review Insider.

Already a Magazine subscriber?

You're automatically an Insider. It's easy to activate or upgrade your account.

Activate Your Account

Become an Insider

It's the new way to subscribe. Get even more of the tech news, research, and discoveries you crave.

Sign Up

Learn More

Find out why MIT Technology Review Insider is for you and explore your options.

Show Me