The Making of a Silicon Solar Cell

Now that we know how solar cells work, let’s take a look at how silicon cells are made. 

Experimental Lab

Purifying the Silicon

When silicon is produced for use in something like a solar cell, the process to make it can cause a small number of impurities. Through an intense heating process, these impurities can be removed to improve the ultimate performance of the solar cell. 

Creating Silicon Wafers

Once the silicon is purified, it is formed into a large block or ingot, and then shaved into wafers about .5 millimeters thick. These thin wafers of material are the foundation of the solar cell, and layers of compounds and materials are added to both sides of the wafer to increase light trapping ability and encourage power delivery. 

Capturing Light

In its natural state, silicon is very shiny! In fact, pure silicon can reflect up to 35 percent of the sunlight. One way the silicon solar cells are enhanced is through a texturizing process used to create small pyramid-shaped 3D patterns that help to reduce the amount of light reflected so that more is absorbed. Using an anti-reflective coating in the manufacturing process, usually, titanium dioxide also reduces energy loss. And the combined effect of texturizing and anti-reflective coating can reduce energy loss to 1%. 

With the main purpose of a solar cell being the capture and transmission of light energy, every step in the process is geared to maximize these goals.