Systems and methods for retrieving residual liquid during immersion lens photolithography

A photolithography system for microfeature workpieces, comprising:

• a support configured to carry a microfeature workpiece;
• a radiation system positioned proximate to the support to direct radiation along a radiation path toward the support;
• and
• an immersion lens system that includes:
• a lens, wherein at least one of the lens and the support is movable relative to the other;
• a liquid supply device having at lease one liquid supply port positioned to deliver a liquid proximate to the lens, the liquid supply device further including a liquid return port positioned proximate to the at least one liquid supply port to remove liquid;
• a gas bearing having at least one nozzle directed toward the support;
• a gas injection device having at least one inwardly directed injection port;
• and
• a controller having instructions to activate selected injection ports depending upon the relative motion between the lens and the support.

A photolithography system for microfeature workpieces, comprising:

• support means for carrying a microfeature workpiece;
• a radiation system positioned proximate to the support means to direct radiation along a radiation path toward the support means;
• and
• an immersion lens system that includes:
• a lens;
• liquid supply means for delivering a liquid to a liquid volume in contact with the lens, and removing liquid from the liquid volume;
• a gas bearing having at least one nozzle directed toward the support;
• gas injection means for directing residual liquid on the microfeature workpiece inwardly into the liquid volume, the gas injection means being located between the at least one nozzle of gas bearing and at least a portion of the liquid supply means;
• and
• a controller having instructions to selectively activate the injection means dependant upon the relative motion between the lens and the support.

A method for irradiating a microfeature workpiece, comprising:

• directing radiation along a radiation path, through a lens and through a liquid volume in contact with the lens to a microfeature workpiece in contact with the liquid volume;
• while moving at least one of the microfeature workpiece and the lens relative to the other, recovering liquid from the liquid volume and replenishing liquid in the liquid volume;
• controlling a spacing between the lens and the microfeature workpiece by providing a gas bearing between the lens and the microfeature workpiece;
• directing residual liquid remaining on a surface of the microfeature workpiece back into the liquid volume, where directing the residual liquid includes directing multiple streams of gas toward the microfeature workpiece from corresponding multiple injection ports;
• and
• selectively directing the gas through different injection ports depending upon the relative motion between the microfeature workpiece and the lens.

A method for irradiating a microfeature workpiece, comprising:

• positioning a lens relative to a microfeature workpiece by directing air between the lens and the microfeature workpiece to form an air bearing;
• directing radiation along a radiation path, through the lens and to the microfeature workpiece through a liquid volume in contact with both the lens and the microfeature workpiece;
• while moving the microfeature workpiece relative to the lens, recovering liquid from the liquid volume, and replenishing liquid in the liquid volume;
• as the microfeature workpiece and the liquid volume move relative to the lens, leaving residual liquid on the microfeature workpiece;
• directing a first portion of the residual liquid remaining on a surface of the microfeature workpiece back into the liquid volume by directing a plurality of nitrogen jets toward the liquid volume through different ports depending upon the relative motion between the microfeature workpiece and the lens;
• and
• removing a second portion of the residual liquid from the workpiece by drawing a vacuum on the second portion through a plurality of vacuum ports.

A photolithography system for microfeature workpieces, comprising:

• a support configured to carry a microfeature workpiece;
• a radiation system positioned proximate to the support to direct radiation along a radiation path toward the support;
• and
• an immersion lens system that includes:
• a lens, wherein at least one of the lens and the support is movable relative to the other;
• a liquid supply device having at least one liquid supply port positioned to deliver a liquid proximate to the lens, the liquid supply device further including a liquid return port positioned proximate to the at least one liquid supply port to remove liquid;
• a gas bearing having at least one nozzle directed toward the support;
• and
• a gas injection device having at least one inwardly directed injection port wherein the at least one gas bearing nozzle forms a portion of a first gas flow path and the at least one injection port forms a portion of a second gas flow path, with a flow of gas along the first flow path being separately controllable from a flow of gas along the second flow path.

A method for irradiating a microfeature workpiece, comprising:

• directing radiation along a radiation path, through a lens and through a liquid volume in contact with the lens to a microfeature workpiece in contact with the liquid volume;
• while moving at least one of the microfeature workpiece and the lens relative to the other, recovering liquid from the liquid volume and replenishing liquid in the liquid volume;
• controlling a spacing between the lens and the microfeature workpiece by providing a gas bearing between the lens and the microfeature workpiece;
• directing residual liquid remaining on a surface of the microfeature workpiece back into the liquid volume, wherein directing the residual liquid includes injecting a gas through at least one injection port that is oriented annularly inwardly toward the liquid volume;
• and
• separately controlling a first flow of gas to the gas bearing and a second flow of gas to the at least one injection port.

A photolithography system for microfeature workpieces, comprising:

• a support configured to carry a microfeature workpiece;
• a radiation system positioned proximate to the support to direct radiation along a radiation path toward the support;
• and
• an immersion lens system that includes:
• a lens, wherein at least one of the lens and the support is movable relative to the other;
• a removable lens cover;
• a liquid supply device having at least one liquid supply port positioned to deliver a liquid proximate to the lens, the liquid supply device further including a liquid return port positioned proximate to the at least one liquid supply port to remove liquid;
• a gas bearing having at least one nozzle directed toward the support;
• a gas injection device having at least one inwardly directed injection port;
• and
• a plurality of recovery ports that are coupleable to a vacuum source, the recovery ports being positioned to releasably secure the cover to the immersion lens system when the immersion lens system is not in use.

A method for irradiating a microfeature workpiece, comprising:

• directing radiation along a radiation path, through a lens and through a liquid volume in contact with the lens to a microfeature workpiece in contact with the liquid volume;
• while moving at least one of the microfeature workpiece and the lens relative to the other, recovering liquid from the liquid volume and replenishing liquid in the liquid volume;
• controlling a spacing between the lens and the microfeature workpiece by providing a gas bearing between the lens and the microfeature workpiece;
• directing a first quantity of residual liquid remaining on a surface of the microfeature workpiece back into the liquid volume, wherein recovering liquid from the liquid volume includes recovering liquid that was directed into the liquid volume;
• and
• removing a second quantity of residual liquid remaining on the surface of the microfeature workpiece by applying a vacuum proximate to the surface of the microfeature workpiece;
• and
• drawing a lens cover with the vacuum when the lens is not in use.

A photolithography system for microfeature workpieces, comprising:

• support means for carrying a microfeature workpiece;
• a radiation system positioned proximate to the support means to direct radiation along a radiation path toward the support means;
• and
• an immersion lens system that includes:
• a lens;
• liquid supply means for delivering a liquid to a liquid volume in contact with the lens, and removing liquid from the liquid volume;
• a gas bearing having at least one nozzle directed toward the support;
• gas injection means including a plurality of injection ports for directing residual liquid on the microfeature workpiece inwardly into the liquid volume, the injection ports being located between the at least one nozzle of the gas bearing and at least a portion of the liquid supply means;
• and
• a plurality of recovery ports positioned proximate to the injection ports that are coupleable to a vacuum source, and wherein the recovery ports are positioned to at least limit movement of a cover when the system is not in use.