Thin-film solar cells are a new type of photovoltaic device for alleviating the energy crisis. They can be manufactured using various inexpensive materials such as ceramics, graphite, and metal sheets as substrates, forming a thin film only a few μm thick to generate voltage. Currently, the highest conversion efficiency can reach 13%. Besides being planar, thin-film solar cells are also flexible enough to be made into non-planar structures, expanding their applications significantly. They can be integrated into buildings or become part of a building structure, making their applications very broad.
Module structure of thin-film solar cells
Thin-film solar modules are composed of a glass substrate, a metal layer, a transparent conductive layer, an electrical functional box, adhesive materials, and a semiconductor layer.
Manufacturing technology of thin-film solar cells
Thin-film solar cells can be manufactured using various inexpensive materials such as glass, plastic, ceramic, graphite, and metal sheets as substrates. The thickness of the thin film that can generate voltage is only a few μm. Therefore, under the same light-receiving area, the amount of raw materials used can be significantly reduced compared to silicon wafer solar cells (the thickness can be more than 90% less than that of silicon wafer solar cells). Currently, the highest conversion efficiency in the laboratory has reached more than 20%, and the highest stable efficiency in mass production is about 13%.
Besides being planar, thin-film solar cells are also flexible enough to be made into non-planar structures, which broadens their applications. They can be integrated with buildings or become part of a building structure. In the manufacturing of thin-film solar cells, various deposition techniques can be used to grow p-type or n-type materials layer by layer. Common thin-film solar cells include amorphous silicon, CuInSe2 (CIS), CuInGaSe2 (CIGS), and CdTe.
Currently, crystalline silicon cells are the primary material used in most of the global photovoltaic industry, with monocrystalline and polycrystalline silicon cells dominating the photovoltaic panel sector. However, the second-generation solar cell market—thin-film solar cells—is quietly emerging, carving out a new niche with its unique advantages such as lightweight and high light transmittance.