CURRENT STATUS OF NewSUBARUNewSUBARU Storage Ring
Y. Shoji
The total machine time in FY2010 was 2608 hrs,
98% of that of FY2010, including the beam downtime. Fig. 1 shows the breakdown. The beam downtime includes not only the down by a failure, butalso off-beam periods by a beam abort or others dueto the beam instability. The normal user time in thisFY, 1489 hrs, was about 90% of that in FY2009.
Time for machine study and special users was 138%of that in FY2009.

Storage Ring Parameters
The machine parameters of the 1.5 GeV storage
ring remain the same as those of the previous year.
They are listed in Table I.
Table I Main parameters of the NewSUBARU
storage ring in FY2008.
Circumference
118.73 m
Bending lattice typemodified DBA
Number of bending cells 6
Straight sections
4m X 4, 15m X 2
Bending radius
3.22 mInjection energy
1.0 GeV
Maximum energy
1.5 GeV
RF frequency
499.955 MHz
Betatron tune
6.30 (H), 2.21 (V)Momentum compaction factor
0.0014
Electron energy
1.0 GeV 1.5 GeV
RF voltage
100 kV 260 kV
Natural energy spread
0.047% 0.072 %Natural emittance
38 nm 67 nm
Maximum beam current 500 mA

Machine Troubles
The machine troubles in FY2010 are listed inTable II. The total down time was only 1.0% of thetotal machine time. It was about 2/3 of that in
FY2009 and 1/3 of that in FY2008. The main
troubles in FY2010 were related to the COD control
system.
We lost 4.6 hours of operation time related to the
newly installed continuous COD correction program.
We had some failures by software bugs and also
some miss-operations of GUI.
We lost 8.5 hours due to a large COD during theacceleration process from 1.0 GeV to 1.5 GeV,
although the current of the steering magnets werechanged according to a fixed pattern control table.
After the experiences of the beam loss by too large
COD at the acceleration, we recognized the shift of
the required current for the steering magnets. Figure
2 shows that the required current had changed day
by day especially at the beginning of the operation
cycle. With this knowledge, the operators reduced
the orbit shift by adjusting the rf frequency and thefailure almost disappeared. However, the reason of
the change is not known.

-0.7
-0.75
-0.8
-0.85
2008/ 11/01

2008/ 07/01-0.9
2008/ 03/01

user time1489 hrs(57%)

2007/ 11/01

machine study &special user time
727 hrs
(28%)

-0.6
-0.65

2007/ 03/01

beam down time by machine troubles
25 hrs (1.0 %)machine tuning
367 hrs
(14%)

-0.55

2007/ 07/01

steering magnet current (A)Operation Status
The ring has two user-time operation modes, 1.0
GeV top-up operation mode and 1.5 GeV operation
mode. Basic operation time is 9:00 - 21:00 of
weekdays. Monday is for machine R&D, Tuesday isfor 1.5 GeV user time, Wednesday and Thursday arefor 1.0 GeV top-up user time, Friday is for 1.0 GeV
or 1.5 GeV user time. Night period or weekend isused for machine study and user time with thespecial mode, single bunch operation and LaserCompton Gamma ray, if necessary.

date (y/m/d)Figure 2: Example of the change of a steering
magnet current after the COD correction. The
average current of six horizontal steering magnets at
dispersion sections is plotted. The values in the same
operation cycles were connected with lines. A
current shift of 0.1 A corresponds to an rf frequency
shift of 2.1 kHz/500 MHz, or a maximum horizontal
displacement of 3.4 mm.

Figure 1: Machine time in FY2010.

1

magnets. They were designed based on 3D fieldcalculation considering the interference with othermagnetic yokes nearby. The commissioning as thesteering magnets was successful. The change of thedeflection angle per current was less than a few %.
The new R&D aiming for the improvement of beam
lifetime started using their multi-pole field windings.

Machine Study and Special User Time
Table III shows the list of machine studies in
FY 2010. One special theme, a research related toa production of Laser-Compton backscattering ray and its use, took about 1/4 of the machine
study time as had been in passed FY.
Most of the study reports are open to the public
on the home page of NewSUBARU.
Accelerator Improvements
The ring had some improvements in FY2009.
Bunch current monitor, installed in FY2008
was organized to a new bucket filling control system.
It controls the bucket-selector for the injection andrealizes a wanted bucket filling.
The COD correction system started continuousworking. It operates slow COD correction routine
for every one minute. Some soft ware bugs were
found and fixed.
Four of the vertical steering magnets were
replaced by multi-element corrector magnets (Figure3). The new magnets worked as vertical steering
magnets with exactly the same parameters of the old
Table IIGroup
Operation

Figure 3: Four vertical steering magnets in thedispersion section were replaced by the multielement corrector magnets.

Machine troubles in FY2010.

Failure/trouble
beam down time (hr)Failure of COD control program
4.6
RF voltage control program trouble
2.2
Operation (others)
RF tuner position error
1.4High radiation at intentional beam abort
0.7
Large COD at 1.5 GeV
8.7
beam loss by a beam instabilities
2.6
Troubles at SPring-8 (delay of starting user time)
2.2
Electric power down by a thunder
2.3(software)

Table III List of machine studies in FY2010. The unit of study time is typically 12 hrs/shift.
R＆D theme and special user mode
responsible person study shift
Parameter tuning for 1.5 GeV acceleration
S. Hashimoto1
Betatron tune feedback system
S. Hashimoto
9
Commissioning of X-ray BPM at BL10
S. Hashimoto4
Beam profile measurement
S. Hashimoto2
Measurement of steering response function
Y. Minagawa
2
Laser-Compton backscattering -rays
S. Miyamoto
21
Confirmation of cancellation table of undulator effect
T. Shinomoto
2
Radiation shield for L4BT beam profile monitor
Y. Shoji1
Vertical beam oscillation at the beam injection
Y. Shoji1
Commissioning of the new profile monitor port SR5
Y. Shoji5
Commissioning of sextupole windings in the invert bends
Y. Shoji
8
Transverse beam matching at the beam injection
Y. Shoji7
Effect of the magnetic shield for the DC septum stray field
Y. Shoji1
Instability suppression by chromaticity modulation
Y. Shoji2
Detection of Coherent Synchrotron Radiation
Y. Shoji4
Measurement of beam orbit oscillation in 10 – 300Hz range
Y. Shoji1
Measurement of coherent betatroon oscillation damping time
Y. Shoji1
Measurement of skew-quadrupole field distribution in the ring
Y. Shoji2
Commissioning of octupole component of the multi-element corrector Y. Shoji1
Measurement of amplitude dependent tune shift
Y. Shoji
2
Ring parameter measurement for better lattice model
Y. Shoji1
Test of low emittance latticeY. Shoji22

Beamlines
Takeo Watanabe and Hiroo Kinoshita
Center for EUVL, LASTI, University of Hyogo

beamline for the usage of the thickness measurement of the
carbon contamination originated to the resist outgassing
during the EUV exposure.
BL02 beamline was constructed for the usage of LIGA
in 2003.
BL05 beamline was constracted in response to ademand in the industrial world, that is enhancement of theanalysis ability in the soft X-ray region with thedevelopment of nanotechnology.
The arrangement of the beamlines in the NewSUBARU
synchrotron radiation facility is shown in Fig.1.

Total nine beamlines are operating in the
NewSUBARU synchrotron facility. Four beamlines of
BL01, BL03, BL06 and BL11 were constructed until 1999.
Three beamlines of BL07, BL09 and BL10 were started theoperation from 2000.
BL03B beamline branched from the BL03 beamline
propose for the usage of the EUVL (extreme ultraviolet
lithography) microscope for the EUVL finished mask
inspection.
BL09B beamline branched from BL09 beamline for theusage of the usage of the EUV interference lithography toevaluate. And BL09C beamline branched from BL09B

Fig. 1 Beamline arrangement in NewSUBARU.

I. BL01
BL01 is a beamline for research and developing newlight sources. This beamline is one of two longstraight section on NewSUBARU. Optical klystron
was installed at this straight section. Upstream side of3

storage ring tunnel was constructed in 2004 for
gamma-ray irradiation experiments. Specificationsof this gamma-ray source are listed in Table 1.

this beamline (BL01B) is intended to be used forvisible and infrared light generated from FEL or SR.
Downstream side of this beamline (BL01A) is used
for laser Compton scattering gamma-rays source.
Gamma-ray beamline hutch just outside of theTable 1. Specification of BL01 gamma beam
CO2 laser
Gamma energy : 1.7 - 4 MeV
Gamma flux* : 9 x106 γ/s
10.52 μm
5W
: 6 x105 γ/s (1.5-1.7 MeV)
(with 3mmφ collimator)
Gamma energy : 17 - 40 MeV
Nd laser
Gamma flux* : 7.5 x106 γ/s
1.064 μm
0.532 μm
: 3 x105 γ/s (15-17 MeV)
5W
(with 3mmφ collimator)*Electron beam energy : 1-1.5 GeV*Electron beam current : 250 mA
gamma-ray beam divergence : 0.5 mrad
II. BL02
x-ray mirrors (plane and cylindrical mirror) and Be film
filters. The horizontal angle of the outgoing SR could beobtained up to 12.5 mrad, which corresponds to thehorizontal size of 220 mm (A4 horizontal size) at the
exposure position. The second characteristic performanceof the beamline is the high efficiency differential pumping
system. This was necessary for maintain the vacuum
difference between the storage ring (<10-9 Pa) and theend-station (<10-9 Pa) at which gasses for substrate coolingwill be introduced in the exposure apparatus.
The flexibility for the shapes and functions of
microstructure will be enlarged by achieving 3D
microfabrication process using multi step exposure atvarious configuration between x-ray mask and substrates.
The relative positions between x-ray mask and substrates,
tilt and rotation angle to the SR incident direction can be
moved simultaneously during SR exposure using 5 axis
stages. The movement of each axis is controlled by the PC
in terms of the scanning speeds, scanning length, andrepetition number. In order to decrease the heat load ofsample substrate suffered during SR irradiation helium
introduction and substrate cooling mechanism were alse
equipped. Specification of spectrometer is listed in Table 2.

The LIGA (abbreviated name of Lithogaphic,
Galvanoformung and Abformung) process which consistsfrom deep x-ray lithography, electroforming, and molding
process is one of the promising candidates for such 3D
micofabrication. More than hundreds aspect ratio for
microstructure can be attained by the usa of the higher
energy x-rays (4-15 keV) from synchrotron radiation (SR)with deeper penetration depth to the photosensitive resist.
In this system we have succeeded to enlarged the exposurearea up to A4 size and the fabrication dimension from
submicron to millimeter by varying the energy of the x-ray
source in accordance with the size of desired microparts.
Micostructure with high aspect ratio over several hundreds
will bi achieved using the x-rays over 10 keV since highenergy x-ray has deep penetration depth to thephoto-sensitive resist materials. Whereas, in the case oflithography for low energy x-rays from 1 keV to 2 keV,submicron structures with high aspect ratio will beachieved using the x-rays mask with precise line-width andthinner absorber, since low energy x-rays has low
penetration depth. Based on this principle, the beamilne for
x-ray exposure have constructed with continuous
selectivity of x-rays frpm 100 eV to 15 keV by using theTable 2. Specification of the LIGA exposure system
OpticsPlane and cylindrical mirror, Be filters
Exposure energy
100 - 2 keV, and 4 – 15 keV
Exposure method
Proximity and multi step exposure
Wafer size
A4 or 8 inch
Exposure area
230 mm(H) ×300 mm(V)
Exposure environment< 1 atm (He-gas)

4III. BL03
BL03 is a beamline for the developing the next
generation lithographic technology so called extreme
ultraviolet lithography (EUVL). The exposure tool isinstalled at the end station. Using this exposure tool, theresearch and development of the next generation
lithography such as the less than 70 nm node is going on
process. The exposure wavelength is 13.5 nm.
The semiconductor industry plays a very important rolein the information technology (IT). In 2006, 256 Gbit
DRAM with a gate length of 70 nm will be demanded in
the IT industry. The extreme ultraviolet lithography(EUVL) is a promise technology for fabricating a finepattern less than 70 nm. To meet this schedule, thistechnology has to be developed in the pilot line until 2004.
As for the practical use, it is very important that both toachieve large exposure area and to fabricate fine patterns.
Therefore, at Himeji Institute of Technology, large
exposure field EUV camera consists of three asphericalmirrors was developed. First in the world, we fabricated 60
nm line and space pattern in the large exposure area of 10
mm×10 mm on a wafer. Furthermore, BL03B beamline
branches from the BL03 beamline propose for the usage of
the EUVL microscope for the EUVL finished mask
inspection.

Table 3. Spectification of the exposure tool (ETS-1)
Imaging optics
Three aspherical mirrors
Exposure wavelength13.5 nm
Numerical aperture
0.1
Demagnification
1/5
Resolution
60 nm
Depth of focus
0.9 µmExposure area (static)
30 mm×1 mm
Exposure area (scanning)
30 mm×28 mm
Mask size
4 inch, 8 inch, and ULE 6025
Wafer size
8 inchExposure environment
In vacuum

IV. BL05
BL05 was constructed in response to a demand in theindustrial world, that is enhancement of the analysis ability
in the soft x-ray region with the development of
nanotechnology. BL05 consists of two branch lines for use
in the wide range from 50 eV to 4000 eV. BL05A and
BL05B are designed to cover the energy range of
1300-4000 eV and 50-1300 eV, respectively. The incident
beam from the bending magnet is provided for two branchlines through different windows of a mask. Therefore,
these two branch lines can be employed simultaneously.

1) The double crystal monochromator was installed at
the BL05A. InSb crystals and Si crystals are prepared for a
double-crystal monochromator. Toroidal mirrors are used
as a pre-mirror and a focusing mirror of BL05A. XAFS
measurement in the total electron yield mode andfluorescence XAFS measurement using SSD (SII Vortex)
can be performed. The fluorescence XAFS spectra can bemeasured for samples at the end station filled with He gas.

Table 4. Monochromator specification
Monochromator
Double crystal monochromator
Monochromator crystals
InSb(111), Si(111)Energy range
1300-4000 eV
E/∆E=3000
Resolution

on BL05B. The optical system consists of a first mirror(M0), a second mirror (M1), an entrance slit (S1), a
pre-mirror (M2), and three kinds of plane grating (G), an
exit slit (S2) and a focusing mirror (M3). The including2) The constant-deviation monochromator consisting of ademagnifying spherical mirror and a varied-line-spacing
plane grating (VLSPG), which can provide high resolution,
simple wavelength scanning with fixed slits, was mounted

5

photoelectron spectrum can be measured using sphericalelectron analyzer (VG Sienta, R3000) in an ultra
high-vacuum chamber. The chambers can be replaced byeach other within 1 hour.

angle of the monochromator is 175°. Two measurement
chambers are prepared at the end station of BL05B. The
XAFS spectra in the total electron yield mode andfluorescence XAFS spectra using SDD (EDAX) can bemeasured in a high vacuum chamber. In addition, theMonochromator
Grating
Energy range
Resolution

Table 5. Monochromator specification
Varied-line-spacing plane grating monochromator
100 l/mm, 300 l/mm, 800 mm/l
50-1300 eV
E/∆E=3000

V. BL06
BL06 has been mainly developed for irradiation
experiments such as photochemical reaction, SR-CVD,
photo-etching, surface modification. The white radiation
beam from bending magnet is introduced to the sample
stage using a pair of mirror, whose incident angle was 3°.
The SR at BL06 sample stage had a continuous spectrum
from IR to soft x-ray, which was lower than 1 keV. A

differential pumping system can be utilized forexperiments in a gas atmosphere, which is difficult in thesoft x-ray region. A sample holder can install four pieces ofsamples at a time. By using heater set in the sample holder,
the sample can be heated from room temperature to 220C.
The temperature of sample is monitored using a Cr-Al
thermocouple mounted on the sample holder.

VI. BL07A and BL07B
This beamline was designed for the development of
new materials by SR technology. This beamline consists of
two branch lines, which are provided with an incident
beam from a 3-m undulator by switching the first mirror.
One of them is a high photon-flux beamline with amultilayered-mirror monochromator for the study of
SR-process (BL07A) and another is a high-resolution
beamline with a varied line spacing grating
monochromator for the evaluation of nano-structure
characteristics by SR-spectroscopy (BL07B). The usefulrange of emitted photons from 50 to 800 eV is covered atboth beamlines. The light source of BL07 is a 3-m lengthplanar undulator, which consists of 29 sets of permanent
magnets, a period length of which is 76 mm. The incident
beam from the undulator is provided for two branch lines
by translational switching of first mirror.

Energyrange(eV)Material

50-60
60-95

Mo/Si

90-140140-194
190-400
400-560

Mo/B4C
Ni/C

1) BL07A
The multilayered-mirror (MLM) monochromator,
which has high reflectivity in the soft X-ray region, wasinstalled at the BL07A. It consists of a switching mirror
chamber, a slit chamber, a MLM monochromator, a filter
chamber and a reaction chamber. To obtain a large photon
flux, we decided to use only first mirror (switching mirror),M0, for focusing. The MLM monochromator is designed tocover an energy range of up to about 800 eV by
combination of three kinds of mirror pairs with 4 kinds offilter. The flux deliver by this design is estimated to be
between a maximum of 1017 photons/s at 95 eV and aminimum 21014 photons/s at 300 eV for a 500 mA ring
current.

Table 6. Summary of BL07A.
Multilayer mirror
spacing
Thickness number of
Ratio
layers
20 nm
11 nm
5 nm

0.8

20

0.5

25

0.5

60

550-800

6E/E

Filtermaterial thickness
Al

100 nm

None



Ag

100 nmCr

500 nmNi

500 nm

6.2 %
3.3 %
2.5 %

focusing mirror (M2). The monochromator is designed tocover the energy range 50-800 eV with three gratings, ofwhich including angle are 168. The VLSPG has been wellknown to obtain high resolution in extreme ultraviolet
region by diminishing various kinds of aberration. The
total resolving power about 3000 can be realized in thewhole energy region.

2) BL07B
The constant-deviation monochromator consisting of ademagnifying spherical mirror and varied line spacing
plane grating (VLSPG), which can provide to highresolution, simple wavelength scanning with fixed slits,
was mounted on BL07B. The optical system consists of afirst mirror (M0), a entrance slit (S1), a premirror (M1),and three kinds of plane grating (G), an exit slit (S2) and a

Table 7. Monocromator specification
Mount type
Hettrick-Underwood type
Grating G1, G2, G3
Plane VLS (600 l/mm, 1200 l/mm, 2400 l/mm)
Energy range
50-150 eV, 150 – 300 eV, 300-800 eVResolving power (E/∆E)～3000

VII. BL9A purpose of this beamline is studies on a soft x-ray
interferometry or a holographic exposure experiment withmaking use of highly brilliant and coherent photon beams
radiated from 11 m long undulator in NewSUBARU.
BL09 consists of M0 mirror, M1 mirror, G grating andM2 and M3 mirror. M0 and M3 mirrors are used forhorizontal deflection and beam convergence, M1 is usedfor vertical beam convergence at the exit slit, and M2 isused for vertical deflection and beam convergence. A
monochromator is constructed by M1 and a plane grating.
The maximum acceptance of the undulator beam is 0.64
mrad in horizontal and 0.27 mrad in vertical. The

acceptance can be restricted by 4-jaw slits equipped at
upstream of the M0 mirror.
BL09B beamline branched from BL09 beamline for theusage of the EUV interference lithography for theevaluation of the exposure characteristics of EUV resist.
Coherence length of 1 mm at the resist exposure position
was achieved using BL09B beamilne. And BL09C
beamline branched from BL09B beamline for the usage ofthe thickness measurement of the carbon contamination
originated to the resist outgassing during the EUV
exposure.

Table 8. Monochromator specification
Mount type
Hettrick-Underwood type
Grating
Plane VLS (900 l/mm)
Energy range
50 – 600 eVResolving power (E/∆E)～3000

VIII. BL10
BL10 is for the global use in the Himeji Institute ofTechnology. M0 mirror is used for horizontal deflection andbeam convergence, M1 is used for vertical beam
convergence at the exit slit, and M2 is used for verticaldeflection and beam convergence. A monochromator isconstructed by M1 and a plane grating. At the beginning,the multiplayers reflectiveity measurement was carried out
at this beamline. The characteristics of this beamline andthe result of the Mo/Si multiplayers measurement are
carried out for the development of the EUVL mask
techmology.
BL10 utilizes a monochromator of the varied line

spacing plane grating monochromator (VLS-PGM). Theline density of the monochromator in central region of thegrating is 600 lines/mm. The reflectometer is a two axis
vacuum goniometer using two Huber goniometers. One
axis carries the sample, which may for examplee be amirror at the center of the reflectometer vacuum tank(-motion). The other (-motion) carries the detector on arotating arm. In addition there are through-cacuum linear
motions to translate the sample in two orthogonal directions(x,y). All motors are controlled by computer. The sample
itself is mounted on a kinematic holder. The controlstage
monochromator rotation, and data analysis were program

7

using LABVIEW software. The reflectivity result obtainedat BL10 has a good agreement with that at LBNL.

Table 9. Monochromator specification
Mount type
Hettrick-Underwood type
Grating
Plane VLS (600 l/mm)
Energy range
50 – 600 eVResolving power (E/∆E)～1000

IX. BL11
A beam line BL11 is constructed for exposure Hard
X-ray Lithography (DXL) in the LIGA (German acronym
for Lithographite Galvanoformung and Abformung)process. LIGA process, that utilizes a useful industrial
application of SR, is one of the promising technologies forfabrication of extremely tall three-dimensional
microstructures with a large aspect ratio. This process wasinvented at the Institut Fur Mikrostrukturtechnik (IMT) of
the Karlstuhe Nuclear Center (KfK) in 1980.
Microstructures with height of over a few hundreds µm
have been widely applied to various fields such as
micro-mechanics, micro-optics, sensor and actuator
technology, chemical, medical and biological engineering,and so on. This beam line was designed by the criteria ;photon energy range 4 keV to 6 keV, a beam spot size on
the exposure stage  505 mm2, a density of total
irradiated photons  1011 photons/cm2. BL11 of anabsorber chamber, a first-mirror chamber (M1), a
second-mirror chamber (M2), a 4-way slit chamber, a Be
window chamber, and an exposure chamber. The second
pre-mirror is bent elliptically using a bending mechanism.

Fine bending adjustment of the M2 mirror can be made in
the UHV by the pulse motor. The LIGA process needs thephoton energies of 3 keV to 6 keV, the optics of a LIGA
beam line generally employ a Pt monolayered-mirror anda Be window, which cuts off low-energy photons. The
reflectivity of a Pt-coated mirror is about 55 % in therange of photon energy from 2 keV to 4 keV, however, it
drops to 30 % at the photon energy of 6 keV. Therefore,
new materials with a high reflectivity must to be found for
Deep X-ray lithography (DXL) in this energy range. We
propose the use of a Ni/W/C multilayered-mirror with agraded d-spacing in the range of photon energy from 3 eV
to 6 keV. The calculated reflectivity of the Ni/W/C
multilayered-mirror is higher than 56 % at the photon
energy of 6 keV with a glazing incident angle of 0.8
degrees, and photons that have higher photon energy than
6 keV can be removed A 200 µm-thick beryllium (Be)window in a Be window chamber is used to separate theultra-high vacuum part from the low vacuum part and to
cut off low-energy photons.

Table 10. Specification of the LIGA exposure system
Exposure method
Proximity exposure
Wafer size
4 inch50 mm(H)×80 mm(V)
Exposure area
Exposure environment< 1atm (He-gas)

8

Center for EUV Lithography
Takeo Watanabe and Hiroo Kinoshita
Center for EUV Lithography,
Laboratory of Advanced Science and Technology for Industry, University of Hyogo

1.

Overview of CELLaboratory of Advanced Science and Technology for Industry, University of Hyogo was established in 1995.
EUVL Lithography development has been carried out since 1995 in University of Hyogo. Especially, utilizing
the full field exposure tool which we developed, for the first time in the world, hp 40 nm resist fine pattern was
replicated with collaborating with ASET in 2000. Following this, in 2001, it was reported that hp 39 nm resist
pattern was replicated by EUV-LLC in USA. Related to these results, Dr. Gordon Moore from Intel Corporation
decided to employ EUVL technology to apply in the high volume manufacturing (HVM) for the advanced
semiconductor devices. Then after, the exposure tools have been developed by the stepper companies, andsimultaneously the development of masks and resists have been carried out
Since 2006, Semiconductor Leading Edge Technologies (Selete) which receives a mandate to develop an
EUVL technology from New Energy and Industrial Technology Development Organization (NEDO) has been
investigated to develop exposure tools such as SFET and EUV1 for the development of the semiconductor
devices. As results, it was concluded that “there is no obstacle to develop EUVL technology for 32 nm node”,
and investigation program will finish in the end of March in 2010.
In our laboratory, concerning of the mask technology, EUV microscope was developed for the mask defectinspection from 2002 to 2007 by the funding from Core Research for Evolutional Science and Technology(CREST), Japan Science Technology Agency (JST). EUV microscope (EUVM) which is only one tool in theworld is placed to use for the mask inspection of the absorber pattern and the mask blanks, and we obtained
many results in collaborating with Selete. In addition, since 2008 for the mask inspection for 22 nm node andbelow, lense-less inspection tool on the basis of EUV coherent scattrometry has been developing in collaboratingwith RIKEN and Osaka University in the CREST program.
Furthermore, concerning of the resist, outgas evaluation during EUV irradiation has been carried out since
2000, and many scientific knowledge was obtained. Recently, the in-situ carbon contamination in the resist
outgas environment by EUV irradiation has been carried out. And for the resist evaluation in 22 nm and 16 nm
nodes, it is certain that EUV interference lithographic tool which we developed has a capability to replicate hp16nm resist pattern.
The market shares of the Japanese company supplying masks and resists for EUVL are high, such as 100% for
the mask and 70% for the resists, respectively. Taking these shares into consideration, since useful equipments
which we have developed in NewSUBARU for the advanced semiconductor devices using an EUVL technology
can be opened for common use, we hope strongly that many companies could use the equipments. Consequently,
it is consider that University of Hyogo can play a significant part of the development for the advanced
semiconductor devices.
As results, “Center for EUV Lithography” is established, and use of NewSUBARU in EUVL technology is
promoted. In addition, the experienced researchers from outside will be invited as a guest researcher of thiscenter, and we will make efforts to receive the user’s comments and requirements to support the EUV
lithographic technology for the practical use.

9

2. The Outline of the beamlines for EUVLThe exposure and evaluation experiments related EUVL are carried out at BL-3, BL-9 and BL-10 beamlinesof the NewSUBARU synchrotron radiation facility in Center for EUV Lithography.
BL-3 (bending magnet as a light sourc): EUV microscope (EUVM) and EUV coherent scattrometry
micropscope (CSM) are installed in this beamiline. EUVM is developed for absorber pattern inpspection for the
EUV finishied mask. CSM is developed for the phase defect inspection of the mask blanks and continously
developing it to achievce more higher resolution in inspection.

IL Exp. tool

EUV IL Beamline

BL-9 (10.8-m-long undulator as a light source): Since monochrometer is installed at the middle of this beamline, high accurate spectroscopic measurement is available using the undulator and the monochrometer.
Especially, EUV interfrence lithograpic exposure system is installed in the clean room at the end of this beamline.
Furthermore, in the additional bemaline which is seperated from the original one, resist outgas evaluation system
and in-situ thickness measuement system for the carbon contamination adhesion under the similar light intensityof the HVM EUV exposure system.
BL-10 (bending magnet as a light source): Since two monochrometers of 600/mm and 1800/mm are installedat the middle of the beamline, a high accurate reflectivity measurement for the optical element such as multilayer
mask is available using this beamline. In addition, the optical constants measurement utilizing the vacuum
chamber for common use is carrying out. In the future, refelctivity measurement of the illumination optics,
multilayer charactreization evaluation, and multilayer evalution using polarized light are planned to use theBL10 beamline.

10Study on High Brightness Operation of NewSUBARU
without RF Shaker
Satoshi Hashimoto, Sayaka Chin and Shuji Miyamoto
LASTI, University of Hyogo
Abstract
We studied the possibility of the high brightness operation of the NewSUBARU electron storage
ring without lattice modification. By turning-off the RF shaker that is used to enlarge the verticalsize and the lifetime of stored electron beams, the brightness can be improved 2.7 times assumingthat the stored current is the same. As the lifetime decreases, the top-up current is also reduced
due to the limitation for the total charge that can be injected to the ring. Using a top-up simulator,
we found that the brightness improvement factor could be 1.6 including the stored current decrease
effect.
Introduction
Beam lifetime of the NewSUBARU electron storage ring is dominated mainly by the Touschek effect at
1.0 GeV operation. The industrial users in our radiation facility such as EUVL lithography and LIGA havebeen performed irradiation experiments and prefer the beam operation with a long beam lifetime and an hightop-up current more than that with an high brightness. To improve the lifetime the ring has been operated
with intentionally enlarged vertical beam size using RF shaker, where amplified white-noise signal is added
to four strip-line electrodes to vertically shake electron beams, and now we achieved the lifetime of 7.4 hrs at
the top-up operation of 220mA.
Recently, increasing number of industrial analysis users in our facility want the high resolution ofsynchrotron radiation and the high brightness operation. Generally speaking, the high brightness operationof storage rings needs re-design of ring lattice and re-arrangement of magnets and vacuum chambers and soon. However, in case of NewSUBARU, there is room for making the brightness higher by an easy way, thatis, the operation without RF shaker.
Laws and regulations on radiation safety restrict the total charge that can be injected from a linac to ourring per eight hours (one shift). This fact means that the reduced beam lifetime causes the reduction of the
top-up current that should be kept constant for eight hours. It is important to evaluate how much thebrightness is improved and how much top-up current is reduced by turning-off RF shaker.
Measurement of Lifetime and Beam Size
The total beam lifetime  is determined by the Touschek lifetime  Tous and the gas scattering
lifetime  gas; 1/  =1/  Tous + 1/  gas. We measured the dependence of the lifetime on RF shaker power asshown in Fig. 1. The inverse lifetime increases according to the inverse square root of the RF shaker power.
Turning-off RF shaker, the lifetime was reduced to 2.1 hrs. The vertical size of electron beams was alsomeasured using a visibility monitor [1]. As shown in Fig. 2, the vertical beam size increases according to
the square root of shaker power, that is, kick strength. From these data, we found that 1/  =0.664 / W +1/  gas, and  gas is about 470 hrs at 1.0Gev, 220 mA.

Fig.1. Lifetime vs. RF shaker power

Fig.2. Vertical beam size vs. RF shaker power

Improved Brightness Estimated by Calculation
The brightness of synchrotron radiation is given by

11

(Brightness)  (Photon Flux) / (source dimensions) / (angular spreads of source).
Following the above relation, the reductions of dimension and angular spread of a photon source makes thebrightness higher. We evaluated equivalent reduction of vertical emittance by turning-off of RF shaker andcalculated the improved brightness using the above equation and SRW [2]. Calculated results show that thebrightness could be improved 2.7 times in case of the same stored current by turning-off RF shaker as shownin Fig. 3.

Fig.3. Calculated improvement of brightness .

Fig. 4. Beam accumulation andtop-up operation in a day

Estimation of the Reduced Top-up Current using Top-up Simulator
The reduced beam size causes the reduction of the Touschek lifetime and the possible top-up current. To
evaluate the maximum top-up current, we developed the top-up simulator [3] that can simulate beam
accumulation and top-up operation including various effects such as injection beam intensity, injection
efficiency and lifetime and so on. Beam accumulation and top-up operation in a typical day is shown in Fig.
4. In our facility a beam accumulation starts at 9 a.m. and if the stored current reaches 220mA the top-up
operation for user time starts. The amount of injected charge is measured at a beam transport line. If theintegrated charge exceeds the limit in one shift (369nC), the safety interlock system stops beam injections.
The integrated value is reset at 8:30, 16:30 and 0:30.
The results of simulation are in good agreement with the realistic operation. Using this simulator, wefound that the maximum top-up current is 135mA in the case of turning-off RF shaker. In other words, theoperation over 135mA can’t keep the top-up current constant until reset time of 14:30.
Considerations
By turning-off RF shaker, the brightness atthe same current increases, but the maximum
top-up current decreases. The brightness
improvement factor including the current
reduction effect is shown in Fig. 5. From
this figure we found that it is possible to makethe brightness 1.6 times higher by simply
turning-off RF shaker.
The high brightness operation without RF
shaker could be one of operation modes in
NewSUBARU, if users require the radiation
with higher quality in our facility.
Fig.5.

Brightness improvement factor

Acknowledgements
We greatly thanks to Dr. T. Harada of LASTI for his cooperation, especially offering the spectrum data of
BL9 and BL10 in NewSUBARU.
References[1] S. Hashimoto et al., LASTI Annual Report, vol. 5, pp.13-14 (2003).
[2] http://www.esrf.eu/Accelerators/Groups/InsertionDevices/Software/SRW[3] S. Chin, Bachelor thesis, University of Hyogo (2010)12