Growth of Highly Doped Silicon Cz-Monocrystals with Alternate Doping Substances

Low resistivity silicon wafers are needed for several substrate materials in semiconductor manufacturing and in the solar industry. Conventionally this is achieved by adding pure boron into the melt. Especially for solar application the costs for pure boron are relatively high. So, the idea is to substitute pure Boron by other substance like boric acid. Two different experiments of Czochralski (Cz) crystal growth with alternative dopants were carried out at Fraunhofer CSP. The different dopants were added to the silicon while charging the machine.