Isolating and purifying the silicon is just the first step in the journey toward making solar cells and ultimately solar panels. We next have to turn the beads of purified silicon into micro-thin, square slices of pure silicon called wafers. Below you can see ultra-pure silicon beads that have been added to a molten batch of silicon used in the Continuous Czochralski Process (CCz Process).
First, we melt the silicon and add different elements to it, a process called doping. Most solar cells are made from P-type silicon, which typically has been doped with the element boron during the manufacturing process. P-type silicon doesn't produce the optimal solar cell, but conventional processes have difficulty using other dopants, so P-type silicon it is for most manufacturers.
Not SunEdison. Our proprietary Continuous Czochralski or CCz process enables the creation of N-type silicon, doped with the element phosphorus. And solar cells made with N-type silicon typically deliver 20% to 40% greater power and energy than conventional P-type solar cells.
The next step is to create an ingot of solid, purified silicon that can be sliced into the micro-thin wafers needed for solar cells. We form the ingot out of a single crystal, drawn from the pool of molten silicon. This results in a perfect crystalline structure, where all the atoms are precisely aligned for higher efficiency.
SunEdison's CCz process produces these ingots more efficiently and cost effectively than any other technology.