The road towards accurate optical width measurements at the industrial level

Bernd Bodermann; Rainer Köning; Detlef Bergmann; Egbert Buhr; Wolfgang Hässler-Grohne; Jens Flügge; Harald Bosse

doi:10.1117/12.2021888

13 May 2013 The road towards accurate optical width measurements at the industrial level

Bernd Bodermann, Rainer Köning, Detlef Bergmann, Egbert Buhr, Wolfgang Hässler-Grohne, Jens Flügge, Harald Bosse

Proceedings Volume 8788, Optical Measurement Systems for Industrial Inspection VIII; 87881S (2013) https://doi.org/10.1117/12.2021888
Event: SPIE Optical Metrology 2013, 2013, Munich, Germany

Abstract

Optical vision systems require both unidirectional and bidirectional measurements for the calibrations and the verification of the tool performance to enable accurate measurements traceable to the SI unit Metre. However, for bidirectional measurements up to now the national metrology institutes are unable to provide internationally recognized calibrations of suitable standards. Furthermore often users are not aware of the specific difficulties of these measurements. In this paper the current status and limitations of bidirectional optical measurements at the industrial level are summarised and compared to state-of-the-art optical linewidth measurements performed at PTB on measurement objects of semiconductor industry. It turns out, that for optical widths measurements at an uncertainty level below 1 μm edge localisation schemes are required, which are based on tool and sample dependent threshold values, which usually need to be determined by a rigorous simulation of the microscopic image. Furthermore the calibration samples and structures must have a sufficient quality, e. g. high edge angle and low edge roughness and the structure materials and their material parameters have to be known. The experience obtained within the accreditation process of industrial labs for width calibrations shows that, in order to be able to achieve a desired measurement uncertainties of about 100 nm, the imaging system needs to have a monochromatic Koehler illumination, numerical aperture larger than 0.5, a magnification greater than 50x and the ability to control the deviation of the focus position to better than 100 nm.

Citation Download Citation

Bernd Bodermann, Rainer Köning, Detlef Bergmann, Egbert Buhr, Wolfgang Hässler-Grohne, Jens Flügge, and Harald Bosse "The road towards accurate optical width measurements at the industrial level", Proc. SPIE 8788, Optical Measurement Systems for Industrial Inspection VIII, 87881S (13 May 2013); https://doi.org/10.1117/12.2021888

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
12 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Calibration

Optical testing

Microscopes

Imaging systems

Edge roughness

Metrology

Objectives

Show All Keywords

Keywords/Phrases

Search In:

Publication Years