NewSUBARU synchrotron radiation facility

BL03 beamline is used for extreme ultraviolet lithography (EUVL). In EUVL which is the most promising advanced lithographic technology for 32 nm node and beyond, mask defect inspection, and resist sensitivity and resist outgas measurement can be carried out.

BL03 beamline consist of three branched beamline such as BL03A, BL03B, and BL03C.
BL03A: EUV resist sensitivity and outgas measurement, and coherent EUV scattrometry microscope for EUV mask defect inspection
BL03B: EUV microscope for the EUV mask defect inspection

M1 Mirror

M2 mirror

Coherent EUV Scattrometry Microscope (CSM) (BL03A)

CSM is for the EUV mask defect inspection and CD measurement of the absorber pattern of the EUV mask. CSM employed lense-less optics as an imaging optics. Diffraction pattern created by illuminating the coherent EUV light on the EUV mask pattern is recorded by a x-ray CCD camera. Applying the reiteration computing method, image of the EUV mask pattern can be reproduced from the diffraction pattern. The absorber pattern CD can be computed from the diffraction intensity distribution, and the repeatability of the CD measurement is 0.1 nm. A 6025 glass reticle which has 150 mm□ in size can be loaded by a loadlock chamber into main vacuum chamber, and whole sample can be evaluated. The sample can be exchanged at approximately 1 hr. CSM system is installed in the clean room and EUV mask can be evaluated without the particle contamination.

Ref.) ”Mask observation results using a coherent extreme ultraviolet scattering microscope at NewSUBARU", Tetsuo Harada, Junki Kishimoto, Takeo Watanabe, Hiroo Kinoshita, Dong Gun Lee, J. Vac. Sci. Technol. B 27, pp. 3203-3207 (2009).

Resist Evaluation Tool (BL03A)

Resist sensitivity and outgas can be measured. Resist sensitivity can be measured by a wavelength spectrum as same as that use in the practical EUV exposure system. The SR light created from the bending is monochromated by the seven time reflection utilizing two Mo/Si multilayer mirrors, and the EUV spot size on a resist is 4 mm×4 mm. The exposure time can be controlled by a fast shutter system, and the sensitivity can be obtained by measuring the remained resist thickness. In addition, resist outgas is measured by quadruple mass spectrometer. Resist process and remained resist thickness measurement are carried out in the class 100 clean room in the NewSUBARU radiation facility.
Ref.) "Novel Evaluation System for Extreme Ultraviolet Lithography Resist in NewSUBARU", Takeo Watanabe, Hiroo Kinoshita, Noriyuki Sakaya, Tsutomu Shoki and Seung Yoon Lee, Jpn. J. Appl. Phys. 44, pp.5556-5559 (2005).

EUV Microscope (BL03B)

EUV mask inspection can be carried out. EUVM consists of the reflection imaging optics and x-ray zooming tube. Mask inspection image magnifies to 30 X by Schwarzschild optics which consists of one concave and one convex spherical mirrors. And by a 10-200X x-ray zooming tube, the image magnify to 300-6000X. A 6025 glass reticle which has 150 mm□ in size can be loaded by a loadlock chamber into main vacuum chamber, and whole sample can be evaluated. The sample can be exchanged at approximately 1 hr. The spatial resolution is 50 nm.
Ref.) "Actinic mask metrology for extreme ultraviolet lithography", H. Kinoshita, T. Haga, K. Hamamoto, S. Takada, N. Kazui, S. Kakunai, and H. Tsubakino, T. Shoki, M. Endo, T. Watanabe, J. Vac. Sci. Technol. B 22, pp. 264-267 (2004).

Carbon Contamination Test Tool (BL09C)

Using the in-situ ellipsometer, the process of carbon contamination build-up is investigated during white photon beam or EUV light irradiation, to EUV resist.

Atomic microscope (AFM) in tapping mode (NanSpecIII)
Zygo Interfereometer (GPI XP-HR)