Photovoltaic cells are made from a variety of semiconductor materials that vary in performance and cost. Basically, there are three main categories of conventional solar cells: monocrystalline semiconductor, the polycrystalline semiconductor, an amorphous silicon thin-film semiconductor. The crystallinityof a material indicates how perfectly ordered the atoms are in the crystal structure. The atoms making up a crystal are repeated in a. This type of semiconductor cell generally has a lower conversion efficiency compared to monocrystalline cells, but manufacturing costs are also lower. The polycrystalline material is. The PV materials previously discussed are all in production, with ongoing research to improve efficiency and lower the cost. Two other types of PV cellsare newer and still largely in the research and. This type of solar panel is noncrystalline and can absorb up to forty times more solar radiation than monocrystalline silicon. Thin-film.