Patent · US Expired

Process and device for in-situ decontamination of a EUV lithography device

US6781685B2 · kind B2 · utility

8Cited by
5References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 6, 2001
Grant dateAug 24, 2004
Priority date
Expiry dateDec 30, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70933
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

EUV lithography devices do indeed have a vacuum or an inert gas atmosphere in their interior, yet the appearance of hydrocarbons and/or other carbon compounds within the device cannot be fully prevented. These carbon compounds lead to the contamination of the optical elements and a resulting loss in reflectivity. In order to counteract this, it has been suggested that while operating the EUV lithography device, the degree of contamination should be constantly monitored, e.g. using quartz crystal microwaves. Depending on the degree of contamination, oxygen is supplied to the interior of the lithography device. The oxygen, in combination with exposure radiation breaks down the contamination while the lithography device is running. The EUV lithography device is thereby equipped with at least one measuring device (3) and a connected control unit (4), which is connected to the oxygen supply (5a).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.