Hemlock Semiconductor is looking worldwide for a place to build a new plant to produce polycrystalline silicon, the key material for making solar cells. The company, a venture of Dow Corning, Shin-Etsu Chemical, and Mitsubishi Materials, hopes to have the plant up and running within five years. Hemlock, which claims to be the world's largest producer of polysilicon, expects demand for the material to grow by 30 to 40% annually over the next 10 years. For the past few months, manufacturers of solar cells have faced severe polysilicon shortages. Both Wacker Chemie and Degussa have announced major polysilicon expansions in Germany. Leading solar cell manufacturer SunPower went as far as providing cash to help DC Chemical build a new polysilicon plant in South Korea (C&EN, July 17, page 22). Hemlock will decide where to set up its new plant depending on energy and other costs and the tax and other incentives it receives. Separately, the firm has been expanding its main site in Hemlock, Mich., where it expects to increase annual capacity to 19,000 metric tons by 2009 from 10,000 metric tons today.