US 2004/0165168 A1Published application

Lithographic apparatus and device manufacturing method

AssigneeASML Netherlands B.V.

InventorHako Botma

Life of this patent

Estimating the term…

Loading patent…

Abstract

A projection beam PB is projected onto a substrate W via a mask MA. The direction dependence of the intensity of the beam at the substrate W is controlled by passing the beam through a series of optical elements 120a-b in front of a pupil plane 14. The intensity distribution as a function of position in the pupil plane 14 determines the angle dependence at the substrate W. The optical elements 120a-b, which are preferably arrays of microlenses (or more particularly DOE's: Diffractive Optical Elements) each define an angle dependence of the intensity of the beam PB. The optical elements 120a-b are each arranged to pass a major part of the beam PB substantially without deflection and a minor part with a deflection angle dependent intensity. The major part of the beam is blocked out of the beam behind the series of optical elements 120a-b. As a result an addition of the effects of upon the intensity in the pupil plane 14 is realized.

Claims18

Dependent claims

A lithographic apparatus comprising:

an illumination system to provide a projection beam of radiation, the illumination system defining an intensity distribution in a pupil plane, the illumination system comprising a first optical element constructed and arranged to deflect the projection beam over a first range of directions with a direction dependent intensity distribution determined by the optical element;
a support structure to support a patterning device, the patterning device serving to pattern the projection beam according to a desired pattern;
a substrate table to hold a substrate;
and
a projection system to project the patterned beam onto a target portion of the substrate;
a second optical element optically following said first optical element in a path of the projection beam, the first optical element and the second optical element each being arranged to pass a major part of the projection beam substantially without deflection, the second optical element deflecting a portion of the major part of the projection beam passed by the first optical element over a second range of directions with a direction dependent intensity distribution;
and
a transmission blocking element to block transmission to the substrate of the part of intensity of the projection beam passed undeflected by both the optical element and the second optical element.

5 more elements

A device manufacturing method comprising:

providing a substrate that is at least partially covered by a layer of radiation-sensitive material;
providing a projection beam of radiation using an illumination system;
deflecting a projection beam of radiation with a first optical element over a range of directions with a direction dependent intensity distribution determined by the optical element and passing a major part of the beam substantially without deflection;
patterning the projection beam with a pattern in its cross-section;
and
projecting the patterned beam of radiation onto a target portion of a layer of radiation-sensitive material on a substrate;
deflecting the passed portion of the projection beam over a further range of directions with a direction dependent intensity distribution with a second optical element and passing a major part of the projection beam substantially without deflection;
and
blocking transmission to the substrate of the part of the projection beam passed undeflected by both the first optical element and the second optical element.

6 more elements

Dependencies are inferred from the claim text.