Experimental results and numeric calculations that have been contributed to a better understanding of how layer growth proceeds in the CISCuT process are given in this work. The heat transfer resistance between the heater and copper tape has been found to mainly determine the temperature of the copper tape during the CISCuT process. From this, more insight into the strongly temperature-dependent precursor formation has been gathered. The initial laver growth model of CISCuT absorber layer growth will be described and the partial solubility of CuInS2, in CuIn-melts has been taken into account. Tape-like CISCuT-based solar cells, with a best efficiency of 5.4% achieved so far on an area of 4 cm(2), are presented.