Euv exposure apparatus with reflective elements having reduced influence of temperature variation

Patent metadata

Field	Value
Publication number	US-2016195818-A1
Application number	US-201615070872-A
Country	US
Kind code	A1
Filing date	Mar 15, 2016
Priority date	Jul 30, 2010
Publication date	Jul 7, 2016
Grant date	—

Abstract

A projection lens of an EUV-lithographic projection exposure system with at least two reflective optical elements each comprising a body and a reflective surface for projecting an object field on a reticle onto an image field on a substrate if the projection lens is exposed with an exposure power of EUV light, wherein the bodies of at least two reflective optical elements comprise a material with a temperature dependent coefficient of thermal expansion which is zero at respective zero cross temperatures, and wherein the absolute value of the difference between the zero cross temperatures is more than 6K.

First claim

1 - 19 . (canceled)

20 . A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising:
a plurality of reflective optical elements M i ; said reflective optical elements M i having respective bodies MB i defining respective reflective surfaces MS i for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with an exposure power of EUV light at a wavelength lying in a wavelength range of less than 50 nm, the EUV light being reflected from said reticle when illuminated by said illumination system; a support unit for passively or actively supporting at least one optical element M k ; a pressure control system for the control of the pressure Δp within a surrounding of said at least one reflective optical element M k ; said control being based on a parameter selected from the group consisting of the temperature of the optical element M k , the time, a parameter which directly or indirectly influence the temperature of the optical element M k , an illumination setting, a change of the reticle, thermally or mechanically induced optical aberration data of the optical element M k or the projection lens and an output parameter from a model; and, said model input including data selected from the group consisting of the temperature of the reflective optical element M k , the time, a parameter which directly or indirectly influences the temperature of the optical element M k , an illumination setting, thermally or mechanically induced optical aberration data of the optical element M k or the projection lens and a change of the reticle.

21 . A projection lens of an EUV-lithographic projection exposure system including a reticle and an illumination system for illuminating the reticle, the projection lens comprising:
a plurality of reflective optical elements M i ; said reflective optical elements M i having respective bodies MB i defining respective reflective surfaces MS i for projecting an object field on said reticle onto an image field on a substrate when said projection lens is exposed with an exposure power of EUV light at a wavelength lying in a wavelength range of less than 50 nm, the EUV light being reflected from said reticle when illuminated by said illumination system; at least one reflective optical element M k including a material having a temperature dependent coefficient of thermal expansion which is zero at a zero cross temperature T 0k ; the body MB k of the optical element M k being semitransparent to an IR radiation; said at least one reflective optical element M k with its body MB k including a coating C on or on almost its entire surface of the body MB k ; and, the coating C reflecting IR radiation inside said body MB k .

22 . A mirror comprising:
a body MB k having a reflective surface MS k ; a material with a temperature dependent coefficient of thermal expansion which is zero at a zero cross temperature T 0k ; said body MB k is at least partly coated with a resistive coating C 2 , wherein the resistive coating C 2 has an electrical resistance suitable to heat the body by electrical resistive heating; and, said mirror being adapted for a projection lens of an EUV-lithographic projection exposure system for projecting an object field on a reticle onto an image field on a substrate if the projection lens is exposed with an exposure power of EUV light with a wavelength in a wavelength range of less than 50 nm.

Assignees

• Zeiss Carl Smt Gmbh
• Asml Netherlands Bv

Inventors

• Baer Norman
• Loering Ulrich
• Natt Oliver
• Wittich Gero
• Laufer Timo
• Kuerz Peter
• Limbach Guido
• Hembacher Stefan
• Walter Holger
• Kwan Yim-Bun-Patrick
• Hauf Markus
• Stickel Franz-Josef
• Van Schoot Jan

Classifications

• G03B27/542

  for copying cameras, reflex exposure lighting · CPC title

• G02B17/0647

  using more than three curved mirrors (G02B17/0668, G02B17/0694 take precedence) · CPC title

• B82Y10/00 Primary

  Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic · CPC title

• G02B5/08

  Mirrors {(vehicle mirrors involving special optical features B60R1/08)} · CPC title

• G02B3/00

  Simple or compound lenses · CPC title