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Ways to Make Solar Cells

Solar cells, from tiny crystalline silicon panels powering watches and small electronics to large solar panel arrays which contribute electricity to homes and electrical grids, have been in use for decades. The needs of a given solar device will determine the type of panel used and the means of solar cell production. Small devices such as pocket calculators can operate on power generated by small cells, while solar power plants make use of large, rigid thin-film modules to collect solar energy. The need to attach solar modules to uneven surfaces, such as the exterior of a solar-powered car, can be met with flexible thin-film modules.

  1. Crystalline Silicon Modules

    • Photovoltaic crystalline cells are composed of thin slips of crystal. These cells can be constructed either from a monocrystalline source (in which a single crystal is used) or a multicrystalline source (in which the materials are taken from a compound of many crystals), but are most commonly constructed from silicon. The silicone slip is treated with a diffusion of n-type dopants to create a photo-reactive component just beneath its surface, then it is coated in an anti-reflective layer to maximize its potential to absorb energy from sunlight. This layer is most commonly made of silicon nitride, but in older cells it was also created with titanium dioxide.

    Rigid Thin-Film Modules

    • Rigid thin-film solar cells are manufactured along with the module that will contain them, producing a one-piece, all-inclusive solar panel. The cells themselves are created directly on glass, with electrical connections built into them, and are then layered between the first glass panel and another panel, along with an encapsulant. The cells that make up rigid thin-film modules are the most commonly used of all solar cell types, and are seen in large solar energy plants as well as home photovoltaic systems.

    Flexible Thin-Film Modules

    • The process for manufacturing flexible thin-film modules is similar to that for rigid thin film, but glass is not used. All of the layers of the cell are deposited on a flexible material made from polyester, polymide film or thin, flexible conductive metals. A colorless fluoropolymer is laminated over the front of the cell and a polymer is applied to the back, to promote bonding with the surface to which the flexible modules will be attached.

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