Atomic layer deposition method for coating flexible substrates

摘要

Systems and methods for atomic layer deposition (ALD) on a flexible substrate involve guiding the substrate back and forth between spaced-apart first and second precursor zones, so that the substrate transits through each of the precursor zones multiple times. Systems may include a series of turning guides, such as rollers, spaced apart along the precursor zones for supporting the substrate along an undulating transport path. As the substrate traverses back and forth between precursor zones, it passes through a series of flow-restricting passageways of an isolation zone into which an inert gas is injected to inhibit migration of precursor gases out of the precursor zones. Also disclosed are systems and methods for utilizing more than two precursor chemicals and for recycling precursor gases exhausted from the precursor zones.

主权项

1. A method for depositing a thin film on a flexible substrate, comprising:
introducing a first precursor gas into a first precursor zone; introducing a second precursor gas into a second precursor zone spaced apart from the first precursor zone, the second precursor gas being different from and reactive with-the first precursor gas; guiding a flexible substrate back and forth between the first and second precursor zones, using a plurality of turning guides at least some of which are located in the first and second precursor zones, and each time through a different one of a series of flow-restricting passageways of an isolation zone that is interposed between the first and second precursor zones, so that:
(i) the substrate transits through the first and second precursor zones and the isolation zone multiple times,(ii) the first precursor gas adsorbs to the surface of the substrate during transit of the substrate through the first precursor zone, and(iii) during a subsequent transit of the substrate through the second precursor zone the second precursor gas reacts with the adsorbed first precursor at the surface of the substrate to thereby deposit a thin film on the substrate; introducing an inert gas into the isolation zone; and generating a first pressure differential between the isolation zone and the first precursor zone and a second pressure differential between the isolation zone and the second precursor zone, the pressure differentials sufficient to inhibit migration of the first and second precursor gases out of the respective first and second precursor zones that results in exposure of the substrate to a reactive mixture of nonadsorbed amounts of the first and second precursor gases.