Abstract:
A method of producing polycrystalline CdTe materials and devices that incorporate the polycrystalline CdTe materials are provided. In particular, a method of producing polycrystalline p-doped CdTe thin films for use in CdTe solar cells in which the CdTe thin films possess enhanced acceptor densities and minority carrier lifetimes, resulting in enhanced efficiency of the solar cells containing the CdTe material are provided.
Abstract:
A process for producing a slightly Cu-poor thin film of Cu(In,Ga)(Se,S)2 comprises depositing a first layer (16) of (In,Ga)x(Se,S)y followed by depositing just enough Cu+(Se,S) or Cux(Se,S) to produce the desired slightly Cu-poor material layer (18). In variation, most, but not all, (about 90 % to 99 %) of the (In,Ga)x(Se,S)y layer (20) is deposited first, followed by deposition of all the Cu+(Se,S) or Cux(Se,S) layer (22) to go near stoichiometric, possibly or even preferably slightly Cu-rich, and then in turn followed by deposition of the remainder (about 1 % to 10 %) of the (In,Ga)x(Se,S)y layer (24) to end with a slightly Cu-poor composition. In yet another variation, a small portion (about 1 % to 10 %) of the (In,Ga)x(Se,S)y is first deposited as a seed layer (26), followed by deposition of all of the Cu+(Se,S) or Cux(Se,S) to make a very Cu-rich mixture layer (28), and then followed deposition of the remainder of the (In,Ga)x(Se,S)y layer (30) to go slightly Cu-poor in the final Cu(In,Ga)(Se,S)2 thin film.
Abstract:
A method of producing polycrystalline CdTe materials and devices that incorporate the polycrystalline CdTe materials are provided. In particular, a method of producing polycrystalline p-doped CdTe thin films for use in CdTe solar cells in which the CdTe thin films possess enhanced acceptor densities and minority carrier lifetimes, resulting in enhanced efficiency of the solar cells containing the CdTe material are provided.