NOVELTY - The device has a first layer adjacent to a non-crystalline substrate or superstrate and made of tellurium, cadmium and zinc. A second layer is arranged adjacent to the first layer and made of tellurium and cadmium. A third layer is arranged adjacent to the second layer and made of tellurium and cadmium. The first layer is chemically doped n-type, and the second and third layers are chemically doped p-type, or the first and second layers are chemically doped p-type, and the third layer is chemically doped n-type.    USE - Photovoltaic device e.g. polycrystalline cadmium telluride p-n junction photovoltaic cell, N-intrinsic-p junction solar cell and reverse p-intrinsic-n junction solar cell for absorbing radiant light energy in non-imaging applications and convert the light energy directly into electrical energy and use as an imaging sensor in cameras to obtain an electrical signal for each portion of an image and for generating electrical power.    ADVANTAGE - The device performs doping of structural layers of solar cell devices with shallow donors and acceptors in situ during epitaxial growth of solar cell device structural layers to provide high doping levels to build improved performance solar cells, thus reducing interstitial or intrinsic dopants by providing substitutional dopants, and hence forming high quality thin film solar cell devices with higher power efficiency and longer lifetime. The device provides polycrystalline growth at high deposition rate, cell architectures that remove the problematic cadmium sulfide window layer, deposition with complete doping control in situ to optimize the cell structure with respect to doping concentrations, compositional grading of heterojunction layers to optimize the cell structure by significant reduction in interface recombination sites, the capability to heavily dope material grown over a superstrate near front and back contacts to create one or more low ohmic contacts, passivation of grain boundaries by heavily doping the grain boundaries to repel minority carriers from the boundary recombination sites and complete deposition rate control to allow deposition interruption for crystallizing anneals and allowing highly reduced growth rate for the initial seed layers in order to optimize grain size.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of a reverse p-n junction solar cell structure.