Influence of baking conditions of doped spin-on glass sources on the formation of laser assisted selective emitters

Our purpose here is to combine the rapid thermal annealing (RTA) of doped spin-on glass films SOG layers and pulsed laser assisted treatments (Nd:YAG) in order to form selective emitters. The phosphorus doped SOG films were first rapid thermal annealed at different temperatures before laser irradiation in defined areas. For a given fluence and repetition rate, the sheet resistance values are seen to strongly depend on the baking temperature. An optimal processing temperature of 850/spl deg/C has been found allowing laser treated area with low sheet resistance values as low has 20 /spl Omega///spl square/ and low doped area (100 /spl Omega///spl square/) on the untreated region. Solar cells with selective emitters made by this technique have shown higher open circuit voltage than for reference cells.