Patent · US Active

Reduced pattern loading for doped epitaxial process and semiconductor structure

US8338279B2 · kind B2 · utility

2Cited by
6References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 30, 2011
Grant dateDec 25, 2012
Priority date
Expiry dateMay 5, 2031

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D84/0128
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A semiconductor substrate having transistor structures and test structures with spacing between the transistor structures smaller than the spacing between the test structures is provided. A first iteratively performed deposition and etch process includes: depositing a first doped epitaxial layer having a first concentration of a dopant over the semiconductor substrate, and etching the first doped epitaxial layer. A second iteratively performed deposition and etch process includes: depositing a second doped epitaxial layer having a second concentration of the dopant higher than the first concentration over the semiconductor substrate, and etching the second doped epitaxial layer. The first concentration results in a first net growth rate over the transistor structures and the second concentration results in a lower, second net growth rate over the test structures than the transistor structures, resulting in reduced pattern loading.

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