A novel mask structure for measuring the defocus of scanner

Lisong Dong; Zhiyang Song; Xiaojing Su; Yayi Wei

doi:10.1117/12.2218764

8 March 2016 A novel mask structure for measuring the defocus of scanner

Lisong Dong, Zhiyang Song, Xiaojing Su, Yayi Wei

Proceedings Volume 9778, Metrology, Inspection, and Process Control for Microlithography XXX; 97782A (2016) https://doi.org/10.1117/12.2218764
Event: SPIE Advanced Lithography, 2016, San Jose, California, United States

Abstract

A new focus monitor mask having novel grating structure is proposed to measure the focus variation of the scanner. The grating pattern composes of transparent line, opaque line, π-phase shift groove and π/2 -phase shift groove with their width ratio equivalent to 1:4:1:2. By using this structure, one of the first order and one of the second order of the diffraction spectrum are eliminated. Therefore, the lithography image is formed by the interference of the zeroth order and the left positive (or negative) 1st and 2nd orders, which is more sensitive to the subtle change of focus. The basic principle and characteristic of the proposed mask is described in this paper. Simulations with the lithography simulator PROLITH shows that the monitoring accuracy is improved more than 25%, compared with the conventional phase grating focus monitor (PGFM). The novel mask proposed in our job has potential to be an efficient candidate for measuring the defocus of scanner in the immersion lithography with hyper NA.

Citation Download Citation

Lisong Dong, Zhiyang Song, Xiaojing Su, and Yayi Wei "A novel mask structure for measuring the defocus of scanner", Proc. SPIE 9778, Metrology, Inspection, and Process Control for Microlithography XXX, 97782A (8 March 2016); https://doi.org/10.1117/12.2218764

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

Photomasks

Diffraction

Phase shifts

Scanners

Lithography

Opacity

Diffraction gratings

Show All Keywords

Keywords/Phrases

Search In:

Publication Years