Super-Skinny Solar Cells
Imagine solar cells so thin, flexible, and lightweight that they could be placed on almost any material or surface.
Three MIT researchers have demonstrated just such a technology: the thinnest, lightest solar cells ever produced. Though it may take years to develop into a commercial product, the laboratory demonstration by MIT professor Vladimir Bulović, research scientist Annie Wang, and doctoral student Joel Jean shows a new approach to making solar cells that could help power the next generation of portable electronic devices.
Bulović, MIT’s associate dean for innovation, says the key to the new approach is a single process to make the solar cell, the substrate that supports it, and a protective coating to shield it from the environment. The substrate is made in place and never needs to be handled, cleaned, or removed from the vacuum chamber in which it is fabricated, thus minimizing exposure to dust or other contaminants that could degrade the cell’s performance.
“The innovative step is the realization that you can grow the substrate at the same time as you grow the device,” Bulović says.

The team used a common flexible polymer called parylene, a widely used plastic coating, as both the substrate and the overcoating, and an organic material called DBP as the primary light-absorbing layer. The entire process takes place in a vacuum at room temperature and does not involve any solvents. (In contrast, conventional solar-cell manufacturing requires high temperatures and harsh chemicals.) In this case, both the substrate and the solar cell are “grown” using established vapor deposition techniques.
The result is an ultrathin solar cell that is exceptionally powerful for its weight. Whereas a typical silicon-based solar module, whose weight is dominated by a glass cover, may produce about 15 watts of power per kilogram of weight, the new cells have already demonstrated an output of six watts per gram—about 400 times higher.
To demonstrate just how thin and lightweight the cells are, the researchers draped a working cell on top of a soap bubble. It didn’t pop.
“It could be so light that you don’t even know it’s there, on your shirt or on your notebook,” Bulović says. “These cells could simply be an add-on to existing structures.”
Keep Reading
Most Popular
A Roomba recorded a woman on the toilet. How did screenshots end up on Facebook?
Robot vacuum companies say your images are safe, but a sprawling global supply chain for data from our devices creates risk.
A startup says it’s begun releasing particles into the atmosphere, in an effort to tweak the climate
Make Sunsets is already attempting to earn revenue for geoengineering, a move likely to provoke widespread criticism.
10 Breakthrough Technologies 2023
These exclusive satellite images show that Saudi Arabia’s sci-fi megacity is well underway
Weirdly, any recent work on The Line doesn’t show up on Google Maps. But we got the images anyway.
Stay connected
Get the latest updates from
MIT Technology Review
Discover special offers, top stories, upcoming events, and more.