Patent · US Active

Methods and apparatus for forming backside power rails

US12002705B2 · kind B2 · utility

0Cited by
2References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 14, 2022
Grant dateJun 4, 2024
Priority date
Expiry dateApr 4, 2042

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/0262
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method that forms a sacrificial fill material that can be selectively removed for forming a backside contact via for a transistor backside power rail. In some embodiments, the method may include performing an etching process on a substrate with an opening that is conformally coated with an oxide layer, wherein the etching process is an anisotropic dry etch process using a chlorine gas to remove the oxide layer from a field of the substrate and only from a bottom portion of the opening, and wherein the etching process forms a partial oxide spacer in the opening and increases a depth of the opening and epitaxially growing the sacrificial fill material in the opening by flowing a hydrogen chloride gas at a rate of approximately 60 sccm to approximately 90 sccm in a chamber pressure of approximately 1 Torr to approximately 100 Torr.

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