Technical Advantages Of Amorphous Silicon Solar Cells

(1) Low cost of materials and manufacturing process
First, amorphous silicon solar cells can save a lot of silicon material. Amorphous silicon has a high light absorption coefficient, especially in the visible light band of 0.3-0.75 μm, its absorption coefficient is an order of magnitude higher than that of single crystal silicon, so it has a higher absorption efficiency of solar radiation than single crystal silicon About 40 times, with a very thin amorphous silicon film can absorb 90% of the useful solar energy. Generally, the thickness of amorphous silicon solar cells is less than 0.5um, while the basic thickness of crystalline silicon solar cells is 240-270um, which is more than 200 times different. Therefore, amorphous silicon solar cells need to save a lot of silicon materials. The material is silane used in the production of high-purity polysilicon. This gas is available in large quantities in the chemical industry and is very cheap.
Due to the low reaction temperature, it can be manufactured at a temperature of about 200°C. Therefore, thin films can be deposited on glass, stainless steel plates, ceramic plates, and flexible plastic sheets, which is easy to produce in large areas and at low cost. The production cost of a single amorphous silicon thin-film solar cell can be reduced to 1.2 US dollars/Wp at present. The cost of laminated amorphous silicon thin-film cells can be reduced to below $1/Wp.
In summary, considering the raw materials and production process, the production cost of amorphous silicon is relatively low, and this has become the biggest advantage of amorphous silicon solar cells.
(2) Short energy return period
Since the raw materials for manufacturing amorphous silicon cells and low-temperature production consume less energy, at each stage, the manufacturing of amorphous silicon solar cells consumes less electricity than the production of monocrystalline silicon solar cells, so its energy return period is shorter. The production of amorphous silicon solar cells with a conversion efficiency of 6% consumes about 1.9 kilowatt-hours of electricity per watt, and the return time after generating electricity is about 1.5-2 years, and the energy return period is short. The power generation return time of other polycrystalline silicon and monocrystalline silicon cells is generally more than 6 years.
(3) Suitable for mass production
Amorphous silicon material is formed by vapor deposition, and the method that has been widely used at present is plasma-enhanced chemical vapor deposition (PECVD) method. This manufacturing process can be completed continuously in multiple vacuum deposition chambers, thereby realizing mass production. The main process (PECVD) of amorphous silicon solar cells using glass substrates is similar to that of TFT-LCD arrays, and the production methods are characterized by high automation and high production efficiency.
(4) Many varieties and wide application
Crystalline silicon can be made on substrates of any shape, and ultra-lightweight solar cells can be prepared on flexible substrates or thin stainless steel and plastic substrates; amorphous silicon solar cells can be made into integrated types, device power, output The voltage and output current can be freely designed and manufactured, and various products suitable for different needs can be produced more conveniently. It is more convenient to produce a variety of products suitable for different needs. Due to the high light absorption coefficient and low dark conductance, it is suitable for the production of low-power power supplies for indoor use, such as watch batteries, calculator batteries, etc.; due to the strong mechanical properties of the silicon mesh structure of the a-Si film, it is suitable for use on flexible substrates. Light-weight solar cells can be made on the ground; flexible and diverse manufacturing methods can manufacture building-integrated batteries, which are suitable for the installation of users' rooftop power stations.
(5) Good high temperature performance
When the operating temperature of the solar cell is higher than the standard test temperature of 25°C, its optimum output power will decrease; the influence of temperature on the amorphous silicon solar cell is much smaller than that of the crystalline silicon solar cell.
(6) Good weak light response and high charging efficiency
The absorption coefficient of amorphous silicon material is in the entire range of visible light, and it is better adapted to low light and strong light in actual use.