Patent · US Expired

Method and systems for improving focus accuracy in a lithography system

US7053984B2 · kind B2 · utility

2Cited by
5References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 7, 2005
Grant dateMay 30, 2006
Priority date
Expiry dateFeb 7, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N21/41415
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A focus system that includes a calibration subsystem and a control subsystem. The control subsystem, which includes a control sensor, is in close proximity to the exposing of an image. The calibration subsystem, which includes a calibration sensor and a control sensor, is located remotely from, or off-axis with respect to, the exposing of an image. By separating calibration and control functions, the functional requirements can be separated into two (or more) types of sensors.

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