Forming n-p junction by irradiation - of film of dopant on a substrate with electrons or photons, to mfr. photovoltaic cells

摘要

Method comprises irradiation using a beam of electron or photons, of a film of dopant deposited on a substrate. The substrate is esp. a p-type wafer, with a thin layer of a dopant which is an electron donor. The beam of electrons or photons has characteristics chosen so that, under the influence of the beam, the dopant atoms are introduced into the atomic structure of the substrate. The substrate may be mono- or polycrystalline Si or GaAs or CdTe. The dopant may be Sb, Bi, Li, AS, P, S, Se, Te, F, Cl, Br or I. The method remedies the problems of producing p-n junctions using dopants with very low solubility limits in Si such as Bi or Sb.