Title: Optical stress generator and detector

Abstract

Disclosed is a system for the characterization of thin films and interfaces between thin films through measurements of their mechanical and thermal properties. In the system light is absorbed in a thin film or in a structure made up of several thin films, and the change in optical transmission or reflection is measured and analyzed. The change in reflection or transmission is used to give information about the ultrasonic waves that are produced in the structure. The information that is obtained from the use of the measurement methods and apparatus of this invention can include: (a) a determination of the thickness of thin films with a speed and accuracy that is improved compared to earlier methods; (b) a determination of the thermal, elastic, and optical properties of thin films; (c) a determination of the stress in thin films; and (d) a characterization of the properties of interfaces, including the presence of roughness and defects.

Inventors:

Maris, Humphrey J ^[1]; Stoner, Robert J ^[2]

---

+ Show Inventor Affiliations

1. Barrington, RI
2. Duxbury, MA

Issue Date:

2002-01-01

Research Org.:

Brown Univ., Providence, RI (United States)

OSTI Identifier:

874491

Patent Number(s):

6400449

Assignee:

Brown University Research Foundation (Providence, RI)

Patent Classifications (CPCs):

G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES

Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

Show more

G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES

G01N21/1702 - {with opto-acoustic detection, e.g. for gases or analysing solids}
G01N2291/02827 - Elastic parameters, strength or force
G01N2291/02881 - Temperature
G01N2291/0426 - Bulk waves, e.g. quartz crystal microbalance, torsional waves
G01N2291/0427 - Flexural waves, plate waves, e.g. Lamb waves, tuning fork, cantilever
G01N29/0681 - {by acoustic microscopy, e.g. scanning acoustic microscopy}
G01N29/2418 - {using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics

Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

Y10S977/834 - Optical properties of nanomaterial, e.g. specified transparency, opacity, or index of refraction
Y10S977/90 - having step or means utilizing mechanical or thermal property, e.g. pressure, heat
Y10S977/901 - having step or means utilizing electromagnetic property, e.g. optical, x-ray, electron beamm
Y10S977/955 - Of thermal property
Y10S977/956 - Of mechanical property

Show less

DOE Contract Number:  

FG02-86ER45267

Resource Type:

Patent

Country of Publication:

United States

Language:

English

Subject:

optical; stress; generator; detector; disclosed; characterization; films; interfaces; measurements; mechanical; thermal; properties; light; absorbed; film; structure; change; transmission; reflection; measured; analyzed; information; ultrasonic; waves; produced; obtained; measurement; methods; apparatus; determination; thickness; speed; accuracy; improved; compared; earlier; elastic; including; presence; roughness; defects; thermal properties; optical stress; stress generator; /356/