Patent · US Expired

Solvent prewet and method and apparatus to dispense the solvent prewet

US6579471B2 · kind B2 · utility

1Cited by
26References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 29, 2001
Grant dateJun 17, 2003
Priority date
Expiry dateAug 29, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/16
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method and apparatus is provided for more efficient application of photoresist to a wafer surface. One aspect of the method comprises applying solvent to the wafer and spinning it to coat the entire wafer surface prior to the application of photoresist. This reduces surface tension on the wafer and reduces the amount of resist required to achieve a high quality film. The apparatus comprises adding a third solenoid and nozzle to the coating unit to accommodate the application of solvent to the center of the wafer surface. The method also describes incorporating a new solvent comprising diacetone alcohol, which is a low-pressure solvent, providing extended process latitudes and reduced material expenditures.

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