Featured Research

from universities, journals, and other organizations

Image sensors out of a spray can

Date:
January 22, 2013
Source:
Technische Universitaet Muenchen
Summary:
Researchers have developed a new generation of image sensors that are more sensitive to light than the conventional silicon versions, with the added bonus of being simple and cheap to produce. They consist of electrically conductive plastics, which are sprayed on to the sensor surface in an ultra-thin layer. The chemical composition of the polymer spray coating can be altered so that even the invisible range of the light spectrum can be captured.

Ultra-thin: Organic sensors can be applied to CMOS chips over large and small surfaces, as well as to glass or flexible plastic films.
Credit: U. Benz / TUM

Researchers from Technische Universitδt Mόnchen (TUM) have developed a new generation of image sensors that are more sensitive to light than the conventional silicon versions, with the added bonus of being simple and cheap to produce. They consist of electrically conductive plastics, which are sprayed on to the sensor surface in an ultra-thin layer. The chemical composition of the polymer spray coating can be altered so that even the invisible range of the light spectrum can be captured. This opens up interesting new development possibilities for low-cost infrared sensors aimed at compact cameras and smartphones .

Image sensors are at the core of every digital camera. Before a snapshot appears on the display, the sensors first convert the light from the lens to electrical signals. The image processor then uses these to create the final photo.

Many compact and cellphone cameras contain silicon-based image sensors produced using CMOS (complementary metal oxide semiconductor) technology. Prof. Paolo Lugli and Dr. Daniela Baierl from TUM have developed a cost-effective process to improve the performance of these CMOS sensors. Their approach revolves around an ultra-thin film made of organic compounds, in other words plastics.

The challenge lay in applying the plastic solution to the surface of the image sensors. The researchers tested spin- and spray-coating methods to apply the plastic in its liquid, solution form as precisely and cost-effectively as possible. They were looking for a smooth plastic film that is no more than a few hundred nanometers thick. Spray-coating was found to be the best method, using either a simple spray gun or a spray robot.

Thin coating with high sensitivity to light

Organic sensors have already proven their worth in tests: They are up to three times more sensitive to light than conventional CMOS sensors, whose electronic components conceal some of the pixels, and therefore the photoactive silicon surface.

Organic sensors can be manufactured without the expensive post-processing step typically required for CMOS sensors, which involves for example applying micro-lenses to increase the amount of captured light. Every part of every single pixel, including the electronics, is sprayed with the liquid polymer solution, giving a surface that is 100 percent light-sensitive. The low noise and high frame rate properties of the organic sensors also make them a good fit for cameras.

Potential for developing low-cost infrared sensors

Another advantage of the plastic sensors is that different chemical compounds can be used to capture different parts of the light spectrum. For example, the PCBM and P3HT polymers are ideal for the detection of visible light. Other organic compounds, like squaraine dyes, are sensitive to light in the near-infrared region.

"By choosing the right organic compounds, we are able to develop new applications that were too costly up until now," explains Prof. Paolo Lugli, who holds the Chair of Nanoelectronics at TUM. "The future uses of organic infrared sensors include driver assistance systems for night vision and regular compact and cellphone cameras. Yet, the lack of suitable polymers is the main hurdle."


Story Source:

The above story is based on materials provided by Technische Universitaet Muenchen. Note: Materials may be edited for content and length.


Journal Reference:

  1. Daniela Baierl, Lucio Pancheri, Morten Schmidt, David Stoppa, Gian-Franco Dalla Betta, Giuseppe Scarpa, Paolo Lugli. A hybrid CMOS-imager with a solution-processable polymer as photoactive layer. Nature Communications, 2012; 3: 1175 DOI: 10.1038/ncomms2180

Cite This Page:

Technische Universitaet Muenchen. "Image sensors out of a spray can." ScienceDaily. ScienceDaily, 22 January 2013. <www.sciencedaily.com/releases/2013/01/130122122409.htm>.
Technische Universitaet Muenchen. (2013, January 22). Image sensors out of a spray can. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2013/01/130122122409.htm
Technische Universitaet Muenchen. "Image sensors out of a spray can." ScienceDaily. www.sciencedaily.com/releases/2013/01/130122122409.htm (accessed October 2, 2014).

Share This



More Matter & Energy News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Japan Looks To Faster Future As Bullet Train Turns 50

Japan Looks To Faster Future As Bullet Train Turns 50

Newsy (Oct. 1, 2014) — Japan's bullet train turns 50 Wednesday. Here's a look at how it's changed over half a century — and the changes it's inspired globally. Video provided by Newsy
Powered by NewsLook.com
US Police Put Body Cameras to the Test

US Police Put Body Cameras to the Test

AFP (Oct. 1, 2014) — Police body cameras are gradually being rolled out across the US, with interest surging after the fatal police shooting in August of an unarmed black teenager. Duration: 02:18 Video provided by AFP
Powered by NewsLook.com
Raw: Japan Celebrates 'bullet Train' Anniversary

Raw: Japan Celebrates 'bullet Train' Anniversary

AP (Oct. 1, 2014) — A ceremony marking 50 years since Japan launched its Shinkansen bullet train was held on Wednesday in Tokyo. The latest model can travel from Tokyo to Osaka, a distance of 319 miles, in two hours and 25 minutes. (Oct. 1) Video provided by AP
Powered by NewsLook.com
Robotic Hair Restoration

Robotic Hair Restoration

Ivanhoe (Oct. 1, 2014) — A new robotic procedure is changing the way we transplant hair. The ARTAS robot leaves no linear scarring and provides more natural results. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins