Atomic layer deposition system for coating flexible substrates

A system for depositing a thin film on a flexible substrate, comprising:

• a first precursor zone into which a first precursor gas is introduced when the system is in use;
• a second precursor zone into which a second precursor gas different from the first precursor gas is introduced when the system is in use;
• an isolation zone interposed between the first and second precursor zones and into which an inert gas is introduced when the system is in use, the isolation zone including a series of flow-restricting passageways opening into the first and second precursor zones and arranged to provide a series of pathways along which a flexible substrate is threaded along a path that traverses back and forth between the first precursor zone and the second precursor zone multiple times and each time through the isolation zone;
• and
• a substrate transport mechanism, including:
• a plurality of first turning guides spaced apart along the first precursor zone, at least some of the first turning guides adapted to support the substrate during a change in a direction of travel of the substrate toward the second precursor zone, and
• a plurality of second turning guides spaced apart along the second precursor zone, at least some of the second turning guides adapted to support the substrate during a change in a direction of travel of the substrate toward the first precursor zone.