Patent · US Expired

Forming thin hard mask over air gap or porous dielectric

US7238604B2 · kind B2 · utility

32Cited by
18References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 24, 2003
Grant dateJul 3, 2007
Priority date
Expiry dateMay 26, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/76826
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A thin hard mask is formed over a semiconductor substrate. The thin hard mask allows diffusion of a sacrificial material or pore-forming agent therethrough to form an underlying air gap or porous dielectric region. The thin hard mask may be a polymer or an initially porous material that may be later densified. The thin hard mask may be used to prevent etch steps used in forming an unlanded via from reaching layers below the hard mask.

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