A one-dimensional optimisation strategy - the Golden Section search method -was applied to optimise the photoelectronic behaviour of amorphous silicon. Within a fixed interval of search (150°C-300°C) the substrate temperature was changed continuously. The transient amplitude resulting from in situ time resolved photoconductivity measurements was monitored and evaluated as the quality value of the search problem. Process apparatus, measurement equipment and computer were closed-loop connected as a first step in Computer Aided Process Optimisation (CAPO). For the system investigated, it was found that a maximum in the quality value results after four search steps.
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