Highly efficient solar cells utilize high-grade silicon wafers to guarantee quality performance. But because of its high-cost various manufacturers are looking for a cheaper alternative. Fortunately, thin silicon wafers—or foil of active silicon on top of inexpensive substrates—work as a great alternative to high-grade silicon in solar cells. Here’s everything you need to know about thin silicon wafers in solar cells.
Adding thin silicon wafers on top of inexpensive substrates can help reduce the need for prime grade silicon wafers on solar cells. They make a great alternative, offering the same efficiency and performance as prime grade silicon. Various methods are being developed to produce cost-effective thin silicon wafers or foils of crystalline Si. One of those methods is the lift-off process. It utilizes a belt furnace and a screen printer only.
The lift-off process begins with a metallic layer printed on top of a crystalline Si wafer. It is then heated in a belt furnace at a high temperature and allowed to cool down slowly to harden it. Once the wafer cools, the difference between the thermal expansion coefficient of the metal and the silicon will create a stress field in the substrate. This stress field can grow and create cracks and fractures in the silicon.
Next, the top layer of the silicon-containing the metal layer separates from the main substrate. The metal layer is then taken out from the silicon foil using a metal-etching solution. This process results in ultra-thin silicon foil. The ultra-thin silicon foils generated are clean and stress-free, meaning, when used in solar cells, they’re highly efficient without any back-surface passivation or surface texturing. Despite the stress involved in the process, the material is highly preserved.
Thin silicon wafers can be used in various applications, including solar cells. If you want to use them in your project or business, you can get them from Wafer World. We offer a wide variety of quality wafers at affordable prices! Contact us to request a quote!