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


Now Available: Innovators Under 35 2013 See The 2013 List »

James Carey, 32

Using “black silicon” to build inexpensive, super-sensitive light detectors


Problem: Silicon has limitations as an optical material. While devices from digital cameras to x-ray detectors take advantage of its ability to absorb electromagnetic radiation, longer wavelengths of light fly right through it. If engineers could make silicon light detectors that "see" more thoroughly into the visible and infrared spectra, relatively inexpensive silicon could replace the costlier, more exotic materials often used in optoelectronics.

Solution: As a graduate student at Harvard, James Carey made thin, super-sensitive light detectors out of "black silicon"--a material discovered accidentally when his colleagues fired a laser at a silicon wafer in the presence of a sulfur-containing gas. Carey demonstrated that the process did more than turn silicon black: it also gave the material the ability to absorb the longer wavelengths of visible and infrared light that thin layers of traditional silicon can't. What's more, it absorbed every wavelength more efficiently than conventional silicon does.

Carey cofounded SiOnyx in Beverl­y, MA, to manufacture black-silicon chips for devices such as inexpensive night-vision equipment and infrared surveillance systems. Other potential applications include better cell-phone cameras and cheaper, more sensitive detectors that could lower the x-ray dose needed for advanced medical imaging. --Anne-Marie Corley

2009 TR35 Winners

Andrea Armani

Sensitive optical sensors detect single molecules

James Carey (video)

Using “black silicon” to build inexpensive, super-sensitive light detectors

Adam Dunkels

Minimal wireless-networking protocols allow almost any device to communicate over the Internet

Kevin Fu (video)

Defeating would-be hackers of radio frequency chips in objects from credit cards to pacemakers  

Andrew Houck

Preserving information for practical quantum computing

Shahram Izadi (video)

An intuitive 3-D interface helps people manage layers of data

Ali Javey

“Painting” nanowires into electronic circuits

Anat Levin

New cameras and algorithms capture the potential of digital images

Pranav Mistry (video)

A simple, wearable device enhances the real world with digital information

Aydogan Ozcan

Inexpensive chips and sophisticated software could make microscope lenses obsolete

Vera Sazonova

World’s smallest resonator could lead to tiny mechanical devices

Elena Shevchenko

Assembling nanocrystals to create made-to-order materials

Dawn Song

Defeating malware through automated software analysis

Andrea Thomaz (video)

Robots that learn new skills the way people do

Adrien Treuille (video)

Complex physics simulations that can run on everyday PCs


More Innovators Under 35: