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School of Illinois Experts Provide Us Little Known Techniques to Create More Efficient Pv panels


While silicon is the market normal semiconductor in almost all electrical products, which includes the solar cells that sun panels utilize to transform sunlight into electricity, it is not really the most efficient material readily available. For example, the semiconductor gallium arsenide and connected substance semiconductors provide close to twice the efficiency as silicon in photo voltaic devices, however they are rarely employed in utility-scale applications because of their high manufacturing price.
 
U. of Illinois. (http://illinois.edu/) teachers J. Rogers and X. Li investigated lower-cost ways to create thin films of gallium arsenide that also made possible flexibility in the types of units they could be incorporated into. 
 
If you can lower substantially the price of gallium arsenide and some other compound semiconductors, then you could develop their range of applications.
 
Typically, gallium arsenide is transferred in a individual thin layer on a little wafer. Either the wanted device is created right on the wafer, or the semiconductor-coated wafer is break up into chips of the desired dimension. The Illinois group made the decision to put in numerous layers of the material on a simple wafer, creating a layered, “pancake” stack of gallium arsenide thin films.
 
If you grow ten levels in one growth, you simply have to fill the wafer a single time. If you do this in ten growths, loading and unloading with temp ramp-up and ramp-down get a lot of time. If you consider what is necessary for each growth – the equipment, the procedure, the time, the people – the overhead saving this solution offers is a considerable price reduction.
 
Next the scientists separately peel off the levels and shift them. To accomplish this, the stacks swap levels of aluminum arsenide with the gallium arsenide. Bathing the stacks in a formula of acid and an oxidizing agent dissolves the levels of aluminum arsenide, freeing the individual small sheets of gallium arsenide. A soft stamp-like system selects up the levels, 1 at a time from the top down, for move to another substrate – glass, plastic material or silicon, depending on the application. Then the wafer could be used again for an additional growth.
 
By performing this it's possible to make considerably more material more rapidly and much more cost effectively. This process could create mass amounts of material, as opposed to merely the thin single-layer way in which it is generally grown.
 
Freeing the material from the wafer additionally opens the chance of flexible, thin-film electronics produced with gallium arsenide or many other high-speed semiconductors. To make units which could conform but still retain high performance, which is significant. 
 
In a paper shared on-line May 20 in the magazine Nature (http://www.nature.com/), the group explains its procedures and demonstrates 3 kinds of devices utilizing gallium arsenide chips produced in multilayer stacks: light products, high-speed transistors and solar cells. The authors also supply a detailed price evaluation.
 
An additional benefit of the multilayer approach is the release from area constraints, especially important for photo voltaic cells. As the levels are eliminated from the stack, they could be laid out side-by-side on an additional substrate to generate a much larger surface area, whereas the standard single-layer process restricts area to the size of the wafer.
 
For solar panels, you need big area coverage to get as much sunshine as possible. In an extreme situation we could grow adequate layers to have 10 times the area of the standard.
 
Up coming, the team plans to explore more prospective product applications and other semiconductor materials that might adapt to multilayer growth.
 
About the Author - Shannon Combs contributes articles for the residential solar power savings weblog, her personal hobby website focused on guidelines to help home owners to conserve energy with sun power.