22P052
Production of EUV by using micro wave Plasma
マイクロ波プラズマを用いたEUV光の生成
Kazuya Hanatani1, Tatsuya Hada1, Tomonari Hattori1 , Hodaka Osawa1, Masami Ohnishi1,Waheed Hugrass2
1
1
花谷和哉 , 羽田達矢 , 服部智成1, 大澤穂高1, 大西正視1, Waheed Hugrass2
1

2

Kansai Univ. 3-3-35, Yamanote-cho, Suita-shi, Osaka 564-8680, Japan,
Univ. Tasmania. School of Computing and Information Systems, Univ. Tasmania, Launceston,
Tasumania 7250, Australia
1
関西大学 〒564-8680 大阪府吹田市山手町3-3-35
2
Univ.Tasmania Newnham Drive, Newnham Tasmania 7250,AustraliaThe manufacture of the next generation LSI needs the EUV light for the semiconductor lithograhy. The
EUV is emitted from the highly ionized Xe plasma. The Xe plasma with the high density and the highelectron temperature is produced by the micro-wave (2.45GHz, TM010) amplified by the cavity, where theQ value may be achieved more than 2,000. The vacuum tube penetrates through the center of the cavity
and is filled with 100Pa Xe gas. The EUV power 1 W is now observed by the 500W magnetron oscillator
which works with the period 60Hz and the duty 20%. More EUV out put is expected by tunning the cavity
and optimizing the gas pressure.

1. Introduction
Present day semiconductor technology is capableof manufacturing transistors with 65 nm features.
The production of next generation chips withfeature as small as 22nm is crucial to the successful
development of extreme ultraviolet (EUV)
photolithography. Two methods such as Discharge
Produced Plasma (DPP) and Laser Produced
Plasma (LPP) have been studied for the sake ofproducing EUV.[1]-[3] A ‘debris’ is produced alongwith the EUV. The microwave produced plasma isproposed for the clean EUV light source.
2. Experimental procedure
Figure 1 illustrates the experimental facility, which
consists of the magnetron, the wave guide, the stabtuner, the cavity, the quarts tube, the vacuum
chamber, the EUV detector (photodiode), theamplifier, and the oscilloscope. The Q-value of thecavity is achieved to be 2850 by TM010 mode. The
cavity is cylindrical. The height is 6cm and theradius is 3cm. The quart tube is set in the center
axis of the cavity. The magnetron output is 500W atthe maximum. The repetition cycle and the duty
factor are changed 10 to 1 kHz and 5% to 100% byusing a function generator. The Xenon gas with thepressure 10-200 Pa. is filled in the vacuum
chamber.
3. Experimental results
Figure 2 is the photo of the plasma produced in thequart tube with the diameter of 5mm in the cavity.
Figure 3 shows the input power, the reflection
power and the out- put voltage of the photodiode.
The cavity is tuned in order to minimize thereflection power by the stab tuner. The EUV power(PEUV) is estimated to be 1W from the signal of thephotodiode by the following equation.
Distance from plasma to a photodiode

PEUV 4π (750)2
1=×= 66.5[W / V ]−3V20
13.3×10 ×106 × 0.4
Acceptance surface

Resistance of an amplifier
Transmissivity

Quantum efficiency

③②⑤④⑥

⑦
①⑧

1:Magnetoron 2: Wave guide 3: Stab tuner
4: Cavity 5:Quarts tube 6:Vacuum chamber
7:Photodiode 8:Oscilloscope
Fig.1. Diagram of experimental facility

4. Conclusions
The micro wave 2.45 GHz has been demonstrated
to produce the clean EUV light in the small cavity
with very high Q value. The experiment is the proofof principle of producing the EUV for thelithographic application with the low cost and thesmall facility. The EUV which satisfies thecommercial application may be produced byincreasing the magnetron power.
References[1] B. Santo: IEEE Spectrum 44 (2007) No.8, 12.
[2] S.R. Das: IEEE Spectrum 45 (2008) No.3, 14.
[3] S.F. Home et al.: Proc. SPIE 6151 (2006) 61510P.

Fig.2. Photo of plasma produced in the quart tube
Input
Reflection
Out-put voltage of the photodiodeFig.3. Measurement waveforms