Projection exposure method and projection exposure apparatus for microlithography

Patent metadata

Field	Value
Publication number	US-2016209754-A1
Application number	US-201615083622-A
Country	US
Kind code	A1
Filing date	Mar 29, 2016
Priority date	Oct 2, 2013
Publication date	Jul 21, 2016
Grant date	—

Abstract

A projection exposure method for exposing a radiation-sensitive substrate with at least one image of a pattern includes providing the pattern between an illumination system and a projection lens of a projection exposure apparatus so that the pattern is arranged in the region of an object plane of the projection lens and can be imaged via the projection lens into an image plane of the projection lens. The image plane is optically conjugate with respect to the object plane, and imaging-relevant properties of the pattern can be characterized by pattern data. The method also includes illuminating an illumination region of the pattern with an illumination radiation provided by the illumination system in accordance with an illumination setting which is specific to a use case and which can be characterized by illumination setting data.

First claim

What is claimed is:

1 . A method of using a projection exposure apparatus comprising an illumination system and a projection lens, the method comprising:
illuminating an illumination region of a pattern with illumination radiation provided by the illumination system in accordance with an illumination setting specific to a use case, the illumination setting being characterized by illumination setting data and imaging-relevant properties of the pattern being characterized by pattern data; determining use case data specific to the use case, the use case data comprising pattern data and/or illumination setting data; using the use case data to determine imaging specification data; controlling optical components of the projection lens based on the imaging specification data to adapt imaging behavior of the projection lens to the use case; and using the projection lens adapted to the use case to image the pattern onto a substrate aid.

2 . The method of claim 1 , further comprising determining at least a portion of the pattern data and/or of the illumination setting data by at least one measurement to acquire data about the projection lens.

3 . The method of claim 1 , wherein:
the pattern data comprise at least core region structure data containing quantitative information about the structure of core regions; the core regions comprise regions having the smallest line spacing and/or the smallest periodicity length of a group of mutually parallel lines in the pattern; and lines of the core region form the core region structure.

4 . The method of claim 1 , wherein the pattern data comprise core region structure orientation data representing an orientation of lines of a core region structure of the pattern.

5 . The method of claim 4 , further comprising deriving the core region structure orientation data from illumination setting data containing information about the orientation of poles of a dipole illumination set on the illumination system.

6 . The method of claim 4 , wherein the pattern data comprise, in addition to the core region orientation data, one or more data selected from the group consisting of:
core region structure position data representing a position of lines of a core region structure within the pattern; peripheral region structure orientation data representing an orientation of lines of a peripheral structure of the pattern; and peripheral region structure position data representing a position of lines of a peripheral structure within the pattern.

7 . The method of claim 1 , further comprising determining imaging specification data with regard to the use case data so that imaging specification data of at least two field points differ with respect to at least one imaging specification.

8 . The method of claim 7 , wherein:
an imaging specification S k has a specification ratio between an imaging specification S k (FP i ) for a first field point in the core region and a corresponding imaging specification S k (FP i ) for a second field point in the peripheral region that deviates from one; and max (S k (FP i )/S k (FP j ),S k (FP j )/S k (FP i ))≧1.5.

9 . The method of claim 8 , wherein the imaging specification S k is described by an odd-order Zernike coefficient or a linear combination of odd-order Zernike coefficients.

10 . The method of claim 7 , wherein:
the imaging specification data comprise at least one structure data selected from the group consisting of core region structure orientation data, core region structure position data, peripheral structure orientation data, and peripheral structure position data; the at least one structure data is such that at least one of the following holds:
there are two field points whose imaging specification data differ in at least one aspect; and
there is one field point at which the wavefront specification for a wavefront for an n th -order wavefront expansion function differs in at least one aspect from the wavefront rotated by an angle of 90°/n.

11 . The method of claim 1 , further comprising:
determining at least one subset of use case data and/or imaging specification data for a use case via an extrinsic data acquisition; communicating the at least one subset of use case data and/or imaging specification data to the control unit of the projection lens, wherein: acquiring the extrinsic data comprises at least one measure from the group consisting of:
interrogation by the user via a user interface;
retrieval from a memory accessible to a control unit of the projection exposure apparatus;
determination from information concerning settings on the illumination system of the projection exposure apparatus; and
determination from information about the mask to be exposed.

12 . The method of claim 1 , further comprising determining at least one subset of use case data for a use case via intrinsic data acquisition by at least one measurement on or in the projection lens, and communicating the at least one subject of use case data for the use case to the control unit of the projection lens.

13 . The method of claim 1 , wherein determining use case data comprises automatedly determining projection radiation data representing at least one property of the projection radiation passing from an object plane of the projection lens in a direction of an image plane of the projection lens.

14 . The method of claim 13 , wherein determining projection radiation data comprises measuring a wavefront of the projection radiation at at least one field point.

15 . The method of claim 13 , wherein determining projection radiation data comprises determining intensity distribution data representing a two-dimensional distribution of radiation intensity of the projection radiation at at least one reference surface lying between the object plane and the image plane in a projection beam path.

16 . The method of claim 15 , wherein at least one optical surface of an optical element in the beam path of the projection lens is used as reference surface.

17 . The method of claim 16 , wherein the optical element is a mirror, and the optical surface is a mirror surface.

18 . The method of claim 15 , wherein, for determining intensity distribution data, a two-dimensional temperature distribution at the reference surface is measured in a spatially resolved manner.

19 . The method of claim 18 , further comprising acquiring the two-dimensional temperature via at least one thermal imaging camera or at least one temperature sensor.

20 . The method of claim 15 , further comprising determining intensity distribution data at a reference surface which lies at or in proximity to a pupil plane of the projection lens, and using the intensity distribution data to determine illumination setting data.

21 . The method of claim 15 , further comprising determining intensity distribution data at a reference surface which lies at or in proximity to a field plane of the projection lens, and using the intensity distribution data to determine pattern data.

22 . The method of claim 15 , wherein:
a first reference surface is arranged at or in proximity to a pupil plane of the projection lens; a second reference surface is arranged at or in proximity to a field plane of the projection lens; and the method further comprises:
determining first intensity distribution data at the first reference surface;
determining second intensity distribution data at the second reference surface; and
using the first and the se

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Bittner Boris
• Wabra Norbert
• Von Hodenberg Martin
• Schneider Sonja

Classifications

• G03F7/70525

  Controlling normal operating mode, e.g. matching different apparatus, remote control or prediction of failure · CPC title

• G03F7/70083 Primary

  Non-homogeneous intensity distribution in the mask plane · CPC title

• G03F7/70891

  Temperature · CPC title

• G03F7/706

  Aberration measurement · CPC title

• G03F7/70258 Primary

  Projection system adjustments, e.g. adjustments during exposure or alignment during assembly of projection system · CPC title