摘要 |
<p>In vapor deposition applications, especially OLED mass production, where it is necessary to measure and/or control the deposition rate of evaporation sources within specific tolerances, a measurement system is adapted to use robust and accurate optical thickness measurement methods at high and low rate sources, so that the thickness of a layer deposited on a substrate can be measured and controlled. A first evaporation source (11) deposits a layer of material on a substrate (20). A mobile element (41) is provided, On which a film is deposited from a second evaporation source (12b) in a deposition location (D1). Subsequently the mobile element is conveyed to a measurement location (D2) where the thickness of the film is measured by a thickness detector (45). The measurement apparatus is arranged to control the deposition of the first evaporation source in dependence on the thickness of the film deposited on the mobile element.</p> |