Patent · US Expired

Method and apparatus for characterization of ultrathin silicon oxide films using mirror-enhanced polarized reflectance fourier transform infrared spectroscopy

US6818894B2 · kind B2 · utility

6Cited by

10References

32Claims

0Family size

Assignee

The Board of Trustees of the University of Illinois · US

Inventors

Christos G. Takoudis · Chicago, US
Zhenjiang Cui · San Jose, US

Key dates

Filing date	Apr 29, 2002
Grant date	Nov 16, 2004
Priority date	—
Expiry date	Jul 4, 2022

Classification

Technology area (CPC H)Electricity
CPC primaryH01L2924/0002
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

Ultrathin silicon oxide films thermally grown on Si(100) are characterized with Mirror-Enhanced Polarized Reflectance Fourier Transform Infrared spectroscopy (MEPR-FTIR). MEPR-FTIR is proposed to effectively probe properties of ultra-thin films. Using a mirror and a polarizer, MEPR-FTIR overcomes the difficulty of weak IR intensities normally encountered in ultrathin gate dielectrics such as SiO2 and the intensity of the silicon oxide longitudinal optical (LO) mode is found to increase by a factor of about 20. Therefore, FTIR spectrometers with sensitivity down to 0.01% may allow even sub-monolayer probing of silicon oxide on Si substrates.

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