manufacture of solar cells

http://bit.ly/13vEGo4 – Solar power is being touted as one of the solutions to the energy needs of a hungry world. This brings up the rather fundamental question of how solar cells are actually manufactured.manufacture of solar cells
The vast majority of solar cells on the market these days are polysilicon. These are the cells you see in panel systems on homes and portable versions on boats and motorhomes. The panels are essentially a grouping of individual cells. A single cell does not produce much electricity, but a group does.manufacture of solar cells
The first step in manufacturing a solar cell is preparation of the silicon. Most cells are created using silicon dioxide. It is first exposed to severe heat in a furnace, which reduces it to a purity of 99 percent. It then is put through another purification process that results in 99.5 percent purity, the grade needed to build cells.
Once the silicon is process, the next step is the crystallization of the silicon. The silicon is melted. During the melting, a material such as boron is added.manufacture of solar cells The specific additive creates the electrical basis of the silicon. In solar cells, this is p-type or positive charged.manufacture of solar cells
At this point, the silicon is in the form of ingots. These are then cut n very thin wafers using computer guided machinery. The depth of the wafers is typically 200 to 300 microns. The wafers are then cleaned and we move to the next step.
Now it is time to actually build the cells. The cells are immersed in a negative charge chemical in water. An anti-reflective layer is then added. This is what makes solar cells and panels look dark, often blue. Silver or aluminum conductors are then attached to the cells so electricity can be conducted out of the cells.