Patent · US Expired

Carbon nanotube memory cell for integrated circuit structure with removable side spacers to permit access to memory cell and process for forming such memory cell

US6955937B1 · kind B1 · utility

83Cited by
12References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 12, 2004
Grant dateOct 18, 2005
Priority date
Expiry dateAug 12, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S977/943
  • WIPO fieldMicro-structural and nano-technology
  • WIPO sectorChemistry

Abstract

A carbon nanotube memory cell for an integrated circuit wherein a chamber is constructed in a layer of a dielectric material such as silicon nitride down to a first electrical contact. This chamber is filled with polysilicon. A layer of a carbon nanotube mat or ribbon is formed over the silicon nitride layer and the chamber. A dielectric material, such as an oxide layer, is formed over the nanotube strips and patterned to form an upper chamber down to the ribbon layer to permit the ribbon to move into the upper chamber or into the lower chamber. The upper chamber is then filled with polysilicon. A silicon nitride layer is formed over the oxide layer and a contact opening is formed down to the ribbon and filled with tungsten that is then patterned to form metal lines. Any exposed silicon nitride is removed. A polysilicon layer is formed over the tungsten lines and anisotropically etched to remove polysilicon on the horizontal surfaces but leave polysilicon sidewall spacers. A silicon oxide layer is deposited over the structure and also anisotropically etched forming silicon oxide sidewall spacers on the polysilicon sidewall spacers. The polysilicon is wet etched with an etchant sele…

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