Sensitivity-limiting factors of at-wavelength EUVL mask blank inspection

Author

Tezuka, Yoshihiro ; Tanaka, Toshihiko ; Terasawa, Tsuneo ; Tomie, Toshihisa

Author_Institution

MIRAI-ASET, Tsukuba, Japan

fYear

2005

fDate

25-28 Oct. 2005

Firstpage

80

Lastpage

81

Abstract

Extreme ultraviolet lithography (EUVL) is one of the promising candidates among several lithography options for hp45nm node and beyond. However, fabrication and qualification of defect-free multilayer mask blanks are critical challenges for the implementation of EUVL. MTRAI developed an at-wavelength dark-field inspection tool for mask blanks using 20× Schwarzschild imaging optics and a backside-illuminated CCD, and demonstrated the detection of multilayer defects accurate to 70nm in width and 2nm in height (Tezuka et al., 2004). We are continuously characterizing the tool aiming at the design of a prototype that can inspect the whole area of a mask blank in two hours.

Keywords

charge-coupled devices; fault diagnosis; inspection; masks; ultraviolet lithography; 2 nm; 70 nm; Schwarzschild imaging optics; at-wavelength EUVL process; backside-illuminated CCD; dark-field inspection tool; extreme ultraviolet lithography; mask blank inspection; multilayer defect detection; multilayer mask blanks; sensitivity-limiting factors; Charge coupled devices; Inspection; Lithography; Nonhomogeneous media; Optical device fabrication; Optical imaging; Optical sensors; Prototypes; Qualifications; Ultraviolet sources;

fLanguage

English

Publisher

ieee

Conference_Titel

Microprocesses and Nanotechnology Conference, 2005 International

Print_ISBN

4-9902472-2-1

Type

conf

DOI

10.1109/IMNC.2005.203747

Filename

1595223