Asml Netherlands B.v.

Luberthus Ouwehand

Nicolaas Antonius Allegondus Johannes Van Asten

Elke Van Loenhout

Lun Kai Cheng

Huibert Blokland

Alexander Charles Franciscus Anna Van Well

Oana Cristina Balan

Machiel Jacobus Johannes Viguurs

Hans Baltus Bakker

Erik Roelof Loopstra

Timotheus Franciscus Sengers

Marcel Beckers

Tjarko Adriaan Rudolf Van Empel

Wilhelmus Josephus Box

Leon Martin Levasier

Willem Herman Gertruda Anna Koenen

Marcel Johannus Elisabeth Hubertus Muitjens

Wouter Onno Pril

Arthur Winfried Eduardus Minnaert

Rob Jansen

Leon Joseph Marie Van Den Schoor

Johannes Mathias Theodorus Antonius Adriens

A level sensor for determining a height of a substrate. In one configuration, the level sensor forms part of a lithographic apparatus that includes a projection lens system. The level sensor generates one or more measurement beams and directs the measurement beam to a measurement spot on a substrate having a first reflecting surface, and produces a reflected measurement beam. The level sensor also generates one or more reference beams. A detector detects both the reflected measurement beam and the reference beam, respectively, and produces a measurement signal and a reference signal, respectively, the measurement signal being indicative for the height at the measurement spot. A processor that receives these signals and corrects the measurement signal based on the reference signal. In one configuration, the level sensor has an optical element arranged to direct the reference beam towards a detection branch via an optical reference path arranged to be insensitive to the position of the projection lens system and the first reflecting surface. In one configuration, the level sensor is configured to direct the measurement beam and reference beam along optical paths that are at least partially substantially equal in at least one of the reference branch and the projection branch.

Method for correcting disturbances in a level sensor light path

A lithographic apparatus is disclosed. The apparatus includes a substrate table constructed to hold a substrate. The substrate table is moveable to transfer the substrate between a substrate measuring position and a substrate processing position. The apparatus also includes a measuring system configured to measure at least one aspect or characteristic of the substrate when the substrate table holds the substrate in the measuring position. The measuring system is configured to direct at least one measuring beam and/or field towards a surface of the substrate. A projection system is configured to project a patterned radiation beam onto a target portion of the substrate when the substrate table holds the substrate in the substrate processing position, and a conditioning system is configured to supply a conditioning fluid to at least part of a path of the measuring beam and/or field of the measuring system to condition the part of the path.

Lithographic apparatus and method for manufacturing a device

The invention relates to a level sensor for determining a height of a substrate. The level sensor generates one or more measurement beam and directs the measurement beam to a measurement spot on the substrate and produces a reflected measurement beam. The level sensor also generates one or more reference beams. A detector detects both the reflected measurement beam and the reference beam, respectively, and produces a measurement signal and a reference signal, respectively, the measurement signal being indicative for the height at the measurement spot. A processor that receives these signals and corrects the measurement signal based on the reference signal. The level sensor has an optical arrangement in a predetermined area close to where the substrate is to be located. The measurement beam and the reference beam propagate along substantially equal optical paths of propagation in the predetermined area. The optical arrangement deviates the reference beam from the substantially equal optical paths of propagation in the predetermined area such that the at least one reference beam does not hit the substrate.

A lithographic projection apparatus including an illumination system configured to provide a beam of radiation, a support configured to support a patterning device, the patterning device configured to impart the beam with a pattern in its cross section, a substrate table configured to hold a substrate, a projection system configured to project the patterned radiation onto a target portion of the substrate, a plurality of level sensors for sensing a level of a substrate carried on the substrate table at a plurality of different positions, and a system for determining the position of the substrate table. Also provided is a controller that is configured to cause relative movement between the substrate and the level sensor array from a first position at which a first measurement is taken to a plurality of overlapping positions at which further measurements are taken, and a calculator for calculating a measure of Z position errors and/or substrate table unflatness and/or a measure of the level sensor position/offset using the plurality of overlapping measurements.

Lithographic apparatus and method for determining Z position errors/variations and substrate table flatness

Growing community of inventors

's-Hertogenbosch, Netherlands

Luberthus Ouwehand