Image Number 3 for United States Patent #4159354.
Thin semiconductor films of compounds from groups III-V of the periodic table suitable for solar cells are formed on low cost substrates by forming on the substrate an intermediate film that is chemically related to but has a lower melting point than the desired semiconductor. The desired semiconductor film is then grown on this intermediate film while it is in a molten condition. The molten intermediate layer isolates the substrate from the desired semiconductor layer so that as that layer grows, large area crystals result. The intermediate film may be a semiconductor III-V compound or may be a group III metal alloy.