Amorphous silicon thin-film solar cells are a type of thin-film solar cell that uses amorphous silicon compounds as its basic component. Based on the different materials used, silicon solar cells can currently be divided into three categories: monocrystalline silicon solar cells, polycrystalline silicon thin-film solar cells, and amorphous silicon thin-film solar cells.
Technical advantages of amorphous silicon thin-film solar cells
1. Low production cost: Due to the low reaction temperature, it can be manufactured at around 200℃, allowing thin films to be deposited on glass, stainless steel plates, ceramic plates, and flexible plastic sheets, facilitating large-area production and resulting in lower costs. The production cost of a single-cell amorphous silicon thin-film solar cell can currently be reduced to $1.2/Wp. The cost of a tandem amorphous silicon thin-film solar cell can be reduced to below $1/Wp.
2. Short energy return period: Amorphous silicon solar cells with a conversion efficiency of 6% consume about 1.9 kWh of electricity to produce, and the time to return the above energy after generating electricity is only 1.5-2 years. [1]
3. Suitable for mass production: Amorphous silicon materials are formed by vapor deposition, and the most widely used method is plasma-enhanced chemical vapor deposition (PECVD). This manufacturing process can be completed continuously in multiple vacuum deposition chambers, thus enabling mass production. The main process (PECVD) of amorphous silicon solar cells using glass substrates is similar to that of TFT-LCD array production, both characterized by high automation and high production efficiency.
In terms of manufacturing methods, there are electron cyclotron resonance, photochemical vapor deposition, DC glow discharge, radio frequency glow discharge, sputtering, and hot filament methods. In particular, radio frequency glow discharge, due to its low-temperature process (~200℃), is easy to realize large-area and large-volume continuous production and has now become an internationally recognized mature technology.
4. Good high-temperature performance: When the operating temperature of a solar cell is 25°C higher than the standard test temperature, its optimal output power will decrease; amorphous silicon solar cells are much less affected by temperature than crystalline silicon solar cells.
5. Good low-light response and high charging efficiency: The absorption coefficient of amorphous silicon material is in the entire visible light range, and it has good adaptability to low light intensity in practical use.
These unique technological advantages give thin-film silicon solar cells broad application prospects in the civilian sector, such as building-integrated photovoltaics, large-scale low-cost power plants, and solar lighting sources. Due to the promising future of amorphous silicon thin-film solar cells, many companies, including Sharp, Q-Cells, and Wuxi Suntech, are entering the amorphous silicon thin-film solar cell field on a large scale, and industry statistics are constantly being updated.
