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Your camera could be about to get a lot smaller.

Researchers have succeeded in making one of the key components of cameras, the charge-coupled device (CCD), just one atom thick. 

And they say it could be employed in ultra-thin two-dimensional imaging devices in the future.  

Graduate student Sidong Lei displays a three-pixel prototype made with atomically thin layers of copper indium selenide (CIS) . The new material developed at Rice shows promise for two-dimensional electronics, possibly paving the way to extremely thin cameras in the future

The research, carried out by scientists at Rice University in Texas, was published in the American Chemical Society journal Nano Letters.

The two-dimensional three-pixel prototype traps electrons when light hits the material, and holds them until released for storage.

And its composition, namely copper indium selenide (CIS), apparently shows extraordinary promise for light detection.

Many modern digital cameras used an image sensor called a charge-coupled device (CCD).

This fingernail-sized silicon chip contains millions of photosensitive diodes, which capture pixels for the photograph.

The charge of each pixel is then converted into a series of numbers, creating a digital image of what the cameras has seen.

Decreasing the size of the CCD, however, could allow for much smaller cameras to be made. 

Sidong Lei, a graduate student involved in the study, said: 'Traditional CCDs are thick and rigid, and it would not make sense to combine them with 2-D elements.

'CIS-based CCDs would be ultrathin, transparent and flexible, and are the missing piece for things like 2-D imaging devices.'

Dr Robert Vajtai, a senior faculty fellow in Rice's Department of Materials Science and NanoEngineering, said CIS pixels are highly sensitive to light because the trapped electrons dissipate so slowly.

'There are many two-dimensional materials that can sense light, but none are as efficient as this material,' he said. 

'This material is 10 times more efficient than the best we've seen before.' 

Many modern digital cameras (stock image shown) used an image sensor called a charge-coupled device (CCD). This fingernail-sized silicon chip contains millions of photosensitive diodes, which capture pixels for the photograph. Decreasing the size of the CCD, however, could allow for much smaller cameras to be made

Rice researchers fabricated a sensor array (illustration shown) to test the two-dimensional compound's ability to capture image information. They started with a thin silicon substrate, fabricated three pairs of titanium/gold electrodes on top of the CIS and then cut the CIS into three sections with a focused ion beam

Because the material is transparent, a CIS-based scanner might use light from one side to illuminate the image on the other for capture.

For medical applications, Mr Lei envisions CIS being combined with other 2D electronics in tiny bio-imaging devices that monitor real-time conditions.

In the experiments for the newly reported study, Lei and colleagues grew synthetic CIS crystals, pulled single-layer sheets from the crystals and then tested the ability of the layers to capture light.

He said the layer was about two nanometers thick and consists of a nine-atom-thick lattice. 

The three-pixel prototype sensor based on CIS, a two-dimensional compound of copper, indium and selenium atoms, showed remarkable potential for its ability to capture and hold light in experiments at Rice. The prototype (shown) was was about two nanometers thick and consists of a nine-atom-thick lattice.

Because it's flexible, CIS could also be curved to match the focal surface of an imaging lens system, perhaps like a camera.

He said this would allow for the real-time correction of aberrations and significantly simplify the entire optical system.