Black silicon is a new electronic material discovered in the latest research that can greatly improve photoelectric conversion efficiency.
In layman's terms, black silicon is to make the silicon wafer black. The silicon wafer is still the original silicon wafer. A layer of paint is used on the surface to reduce reflection, so that the silicon wafer looks like It's black. The production method is to brush the coating to make the surface have ridges one by one. The main component of the coating is silica. When we look at the existing silicon cells, they are all blue with a grille on them. Such silicon wafers have been passivated. The purpose of passivation is to reduce reflection and remove dangling bonds, but we still look blue. Colorful and bright, black silicon is much better than the existing passivation. Existing passivation requires strict temperature requirements and requires vacuum.
This black silicon material captures almost all sunlight. It acts like a light-absorbing sponge, absorbing both visible and infrared light. This material can improve the efficiency of light use and generate hundreds of times more current than traditional silicon materials. In addition, black silicon can reduce the amount of silicon used in light sensors, making products cheaper, smaller and lighter.
Recently, professional equipment company Natcore Technology has combined diffusion emitter technology "Black Silicon" with Natcore's liquid phase deposition (LPD) technology, and has been approved by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) granted an exclusive patent license. Natcore scientists and NREL researchers say the black silicon production process can reduce average reflectivity to less than 1.5%, while current advanced anti-reflective coatings can only reduce average reflectivity to about 6%. The company aims to have the technology commercially available in 2012.
Dr. Dennis Flood, chief technology officer of Natcore, said: "Natcore has the ability to achieve passivation of black silicon cells through liquid deposition technology, which is what we lacked in the past. This technology can promote black silicon cells. Silicon reaches its potential. Before Natcore’s passivation technology, coated cells had to be placed in a furnace at 1,000 degrees to create the thermal oxide layer.”
According to Natcore, its LPD silica coating. While achieving passivation, no additional heat treatment process is required, thereby reducing process costs and improving battery efficiency. Chuck Provini, President and CEO of Natcore, said: “We combine NREL’s black silicon technology with LPD and passivation technology to optimize the mixing process and integrate them into the AR-Box to achieve ultra-low reflection. Efficient full liquid phase process to increase the yield of high-performance silicon solar cells."