Featured Research

from universities, journals, and other organizations

Ultrafast laser 'scribing' technique to cut cost, hike efficiency of solar cells

Date:
March 9, 2011
Source:
Purdue University
Summary:
Researchers are developing a technology that aims to help make solar cells more affordable and efficient by using a new manufacturing method that employs an ultrafast pulsing laser.

This image, taken with a scanning electron microscope, shows a microchannel that was created using an ultrafast-pulsing laser.
Credit: Purdue University School of Mechanical Engineering image/Yung Shin

Researchers are developing a technology that aims to help make solar cells more affordable and efficient by using a new manufacturing method that employs an ultrafast pulsing laser.

Related Articles


The innovation may help to overcome two major obstacles that hinder widespread adoption of solar cells: the need to reduce manufacturing costs and increase the efficiency of converting sunlight into an electric current, said Yung Shin, a professor of mechanical engineering and director of Purdue University's Center for Laser-Based Manufacturing.

Critical to both are tiny "microchannels" needed to interconnect a series of solar panels into an array capable of generating usable amounts of power, he said. Conventional "scribing" methods, which create the channels mechanically with a stylus, are slow and expensive and produce imperfect channels, impeding solar cells' performance.

"Production costs of solar cells have been greatly reduced by making them out of thin films instead of wafers, but it is difficult to create high-quality microchannels in these thin films," Shin said. "The mechanical scribing methods in commercial use do not create high-quality, well-defined channels. Although laser scribing has been studied extensively, until now we haven't been able to precisely control lasers to accurately create the microchannels to the exacting specifications required."

The researchers hope to increase efficiency while cutting cost significantly using an "ultrashort pulse laser" to create the microchannels in thin-film solar cells, he said.

The work, funded with a three-year, $425,000 grant from the National Science Foundation, is led by Shin and Gary Cheng, an associate professor of industrial engineering. A research paper demonstrating the feasibility of the technique was published in Proceedings of the 2011 NSF Engineering Research and Innovation Conference in January. The paper was written by Shin, Cheng, and graduate students Wenqian Hu, Martin Yi Zhang and Seunghyun Lee.

"The efficiency of solar cells depends largely on how accurate your scribing of microchannels is," Shin said. "If they are made as accurately as possibly, efficiency goes up."

Research results have shown that the fast-pulsing laser accurately formed microchannels with precise depths and sharp boundaries. The laser pulses last only a matter of picoseconds, or quadrillionths of a second. Because the pulses are so fleeting the laser does not cause heat damage to the thin film, removing material in precise patterns in a process called "cold ablation."

"It creates very clean microchannels on the surface of each layer," Shin said. "You can do this at very high speed, meters per second, which is not possible with a mechanical scribe. This is very tricky because the laser must be precisely controlled so that it penetrates only one layer of the thin film at a time, and the layers are extremely thin. You can do that with this kind of laser because you have a very precise control of the depth, to about 10 to 20 nanometers."

Traditional solar cells are usually flat and rigid, but emerging thin-film solar cells are flexible, allowing them to be used as rooftop shingles and tiles, building facades, or the glazing for skylights. Thin-film solar cells account for about 20 percent of the photovoltaic market globally in terms of watts generated and are expected to account for 31 percent by 2013.

The researchers plan to establish the scientific basis for the laser-ablation technique by the end of the three-year period. The work is funded through NSF's Civil Mechanical and Manufacturing Innovation division.

Information about photovoltaic cells is available from the U.S. Department of Energy's National Renewable Energy Laboratory at http://www.nrel.gov/learning/re_photovoltaics.html


Story Source:

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


Cite This Page:

Purdue University. "Ultrafast laser 'scribing' technique to cut cost, hike efficiency of solar cells." ScienceDaily. ScienceDaily, 9 March 2011. <www.sciencedaily.com/releases/2011/03/110308173244.htm>.
Purdue University. (2011, March 9). Ultrafast laser 'scribing' technique to cut cost, hike efficiency of solar cells. ScienceDaily. Retrieved December 19, 2014 from www.sciencedaily.com/releases/2011/03/110308173244.htm
Purdue University. "Ultrafast laser 'scribing' technique to cut cost, hike efficiency of solar cells." ScienceDaily. www.sciencedaily.com/releases/2011/03/110308173244.htm (accessed December 19, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Friday, December 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Building Google Into Cars

Building Google Into Cars

Reuters - Business Video Online (Dec. 19, 2014) Google's next Android version could become the standard that'll power your vehicle's entertainment and navigation features, Reuters has learned. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
AP Review: Nikon D750 and GoPro Hero 4

AP Review: Nikon D750 and GoPro Hero 4

AP (Dec. 19, 2014) What to buy an experienced photographer or video shooter? There is some strong gear on the market from Nikon and GoPro. The AP's Ron Harris takes a closer look. (Dec. 19) Video provided by AP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
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