Patent · US Expired

Method of creating a tapered via using a receding mask and resulting structure

US7081408B2 · kind B2 · utility

13Cited by
2References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 28, 2004
Grant dateJul 25, 2006
Priority date—
Expiry dateOct 28, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/0002
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Embodiments of a method of forming a tapered via using a receding mask are disclosed. In one embodiment, an etch mask formed on a substrate includes a first aperture in a first photoresist layer and a second, larger aperture in an overlying second photoresist layer. Peripheries of the first and second apertures may be tapered as a result of an out-of-focus exposure. An etching process may be performed to create a tapered via in the substrate, and during this etching process, the first, relatively thinner photoresist layer will recede outwardly toward the aperture in the second photoresist layer. Other embodiments are described and claimed.

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