Characterization of acoustic cavitation from a megasonic nozzle transducer for photomask cleaning

Nicolas Candia; Claudio Zanelli; Johann Brunner; Joachim Straka; Zhenxing Han; Sam Howard; Petrie Yam

doi:10.1117/12.2281272

16 October 2017 Characterization of acoustic cavitation from a megasonic nozzle transducer for photomask cleaning

Nicolas Candia, Claudio Zanelli, Johann Brunner, Joachim Straka, Zhenxing Han, Sam Howard, Petrie Yam

Proceedings Volume 10451, Photomask Technology 2017; 1045114 (2017) https://doi.org/10.1117/12.2281272
Event: SPIE Photomask Technology and EUV Lithography, 2017, Monterey, California, United States

Abstract

Megasonic agitation continues to be used in advanced 193i and EUV photomask cleaning processes. The trend to adopt higher frequencies is driven by the need to control a tighter process window with shrinking feature sizes and a zerotolerance defect requirement. Despite continued use of megasonics, the effect of the acoustic field applied to the mask substrate remains unclear. Photomask cleaning is a dynamic process with many parameters that contribute to the particle removal efficiency and pattern damage. These include transducer type, transducer position, drive frequency, power setting, flow rate, chemistry, gas concentration, etc. To add to the complexity, when the acoustic waves from the transducer interact with a quartz mask the energy may reflect from, transmit through, or couple into the substrate. An in-situ measurement of the acoustic field, as present at the feature location, is required to correlate acoustic parameters with cleaning performance. This work introduces a photomask-shaped cavitation sensor capable of measuring the absolute pressure from the direct field, stable cavitation, and transient cavitation present at the surface. In contrast to previous work characterizing skirt-type transducers, this measurement instrument is sensitive to higher drive frequencies while withstanding concentrated pressure levels from nozzle transducers. Here, a megasonic system with dual nozzle transducers at 5 MHz and 3 MHz was evaluated. The aim of the study is to better understand the acoustic properties from different types of transducers for process development and monitoring in the quest to correlate with photomask cleaning.

Citation Download Citation

Nicolas Candia, Claudio Zanelli, Johann Brunner, Joachim Straka, Zhenxing Han, Sam Howard, and Petrie Yam "Characterization of acoustic cavitation from a megasonic nozzle transducer for photomask cleaning", Proc. SPIE 10451, Photomask Technology 2017, 1045114 (16 October 2017); https://doi.org/10.1117/12.2281272

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
9 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Cavitation

Transducers

Sensors

Acoustics

Acoustic cavitation

Photomasks

Liquids

Show All Keywords

Keywords/Phrases

Search In:

Publication Years