LOW-DAMAGE SURFACE TREATMENT BY GAS CLUSTER-ION BEAMS

Low-damage irradiation effects of gas cluster-ion beams have been studied at acceleration voltages below 20 kV. The surfaces of targets have been smoothened significantly by CO 2-cluster-ion irradiation at normal incidence. Si substrate surfaces have been cleaned and exhibited low damage after CO 2- and Ar-cluster-ion irradiation at low doses. In the case of CO 2-cluster-ion irradiation, SiO 2 film of about 5.5-nm thickness have grown on Si substrate at room temperature. A damaged layer of less than 2.5-nm thickness has been formed underneath the SiO 2 film.

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Irradiation Effects of Ar-Cluster Ion Beams on Si Surfaces

MRS Proceedings ◽

10.1557/proc-316-1005 ◽

1993 ◽

Vol 316 ◽

Cited By ~ 10

Author(s):

G. H. Takaoka ◽

G. Sugahara ◽

R. E. Hummel ◽

J. A. Northby ◽

M. Sosnowski ◽

...

Keyword(s):

Cluster Size ◽

Ion Beams ◽

Cluster Ions ◽

Irradiation Effects ◽

Damage Layer ◽

Ion Energies ◽

Cluster Ion Beams ◽

Cluster Ion ◽

The Mean

ABSTRACTThe effects of energetic Ar cluster ion impacts on Si(111) surfaces have been studied for cluster energies up to l5keV. The mean cluster size was about 1000 atoms, and the smaller sizes could be systematically excluded. Si samples irradiated at different cluster ion energies were analyzed by RBS, ellipsometry, and differential reflectometry. Implantation of Ar in samples irradiated with cluster ions was found by RBS to be detectable, but very small in comparison with samples irradiated with monomer ions of the same energy. The thickness of the damage layer as measured by both ellipsometry and differential reflectometry was also much smaller in the cluster ion irradiated samples.

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Irradiation effects of liquid cluster ion beams on silicon surfaces

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2006.12.035 ◽

2007 ◽

Vol 201 (19-20) ◽

pp. 8628-8631 ◽

Cited By ~ 2

Author(s):

Gikan H. Takaoka ◽

Masakazu Kawashita ◽

Hidetaka Noguchi ◽

Kazuya Nakayama

Keyword(s):

Ion Beams ◽

Silicon Surfaces ◽

Irradiation Effects ◽

Cluster Ion Beams ◽

Cluster Ion

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Surface Planarization with Gas Cluster Ion Beams and Application to Wide-Bandgap Semiconductors

International Journal of Automation Technology ◽

10.20965/ijat.2018.p0170 ◽

2018 ◽

Vol 12 (2) ◽

pp. 170-174 ◽

Cited By ~ 1

Author(s):

Noriaki Toyoda ◽

Keyword(s):

Wide Bandgap ◽

Ion Beams ◽

Cluster Ions ◽

Irradiation Effects ◽

Atomic Ions ◽

Smoothing Effects ◽

Cluster Ion Beams ◽

Cluster Ion ◽

Multiple Collisions ◽

Bandgap Semiconductors

In this study, the fundamental sputtering effects of gas cluster ion beams (GCIBs), especially for surface planarization, are reported. Because gas cluster ions are aggregates of thousands of gas atoms, the collision process for a GCIB, with dense and multiple collisions, differs from that of atomic ions via collision cascading; thus, GCIBs have many unique irradiation effects. Among them, the low-damage and surface smoothing effects are beneficial for the planarization of wide-bandgap semiconductor wafers. The planarization of SiC, diamond, and GaN has been demonstrated using GCIB irradiation.

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Irradiation Effects of Gas Cluster Ion Beams on Co–Fe Films

Japanese Journal of Applied Physics ◽

10.7567/jjap.52.06gf01 ◽

2013 ◽

Vol 52 (6S) ◽

pp. 06GF01 ◽

Cited By ~ 1

Author(s):

Noriaki Toyoda ◽

Akihiro Fujimoto ◽

Isao Yamada

Keyword(s):

Ion Beams ◽

Irradiation Effects ◽

Cluster Ion Beams ◽

Cluster Ion

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Irradiation Effects of Methanol Cluster Ion Beams on Solid Surfaces

MRS Proceedings ◽

10.1557/proc-1020-gg07-07 ◽

2007 ◽

Vol 1020 ◽

Cited By ~ 2

Author(s):

Gikan Takaoka ◽

Masakazu Kawashita ◽

Takeshi Okada

Keyword(s):

Ion Irradiation ◽

Ion Beams ◽

Solid Surfaces ◽

Reaction Products ◽

Si Substrates ◽

Chemical Sputtering ◽

Cluster Ion Beams ◽

Cluster Ion ◽

Sputtering Yield ◽

Acceleration Voltage

AbstractIn order to investigate the interactions of methanol cluster ion beams with solid surfaces, Si substrates and SiO2 films were irradiated at different acceleration voltages. The sputtered depth increased with increase of the acceleration voltage. When the acceleration voltage was 9 kV, the sputtered depths of Si and SiO2 at a dose of 1×1016ions/cm2 were 1497.1 nm and 147.8 nm, respectively. The selectivity between Si and SiO2 surfaces arose from the volatility of the reaction products. Furthermore, the sputtering yield for the Si surface was approximately seven hundreds times larger than that by Ar monomer ion beams. This suggested that chemical sputtering was predominant for the methanol cluster ion irradiation. In addition, the etching and cleaning process by the methanol cluster ion irradiation was performed on the Si surfaces contaminated with a small amount of metal particles such as Au and Al. Thus, methanol cluster ion beams have unique characteristics such as surface etching and cleaning with high sputtering yield and smooth surface.

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High-speed Processing with Cluster Ion Beams

MRS Proceedings ◽

10.1557/proc-792-r9.29 ◽

2003 ◽

Vol 792 ◽

Cited By ~ 2

Author(s):

Toshio Seki ◽

Jiro Matsuo

Keyword(s):

High Speed ◽

Ion Irradiation ◽

Ion Beam ◽

Ion Beams ◽

High Rate ◽

Cluster Ions ◽

Cluster Ion Beams ◽

Cluster Ion ◽

Sputtering Yield ◽

Reactive Cluster

ABSTRACTCluster ion beam processes can produce high rate sputtering with low damage in comparison with monomer ion beam processes. Especially, it is expected that extreme high rate sputtering can be obtained using reactive cluster ion beams. High current SF6 cluster ion beams were recently obtained with new modifications in the basic cluster ion beam technique. The cluster size distribution was measured with Time-of-Flight (TOF) method and the mean size of cluster was about 500 molecules. Si substrates were irradiated with SF6 cluster ions at the acceleration energy of 5–45 keV. Sputtering yield with SF6 cluster ions was increased with acceleration energy and was about 2300 atoms/ion at 45 keV. The sputtering yield was about 1000 times higher than that of Ar monomer ions and was also higher than that of Ar cluster ions. It was found that reactive sputtering occurred with SF6 cluster ion irradiation. These results indicate that high-speed fabrication can be realized with reactive cluster ion irradiation at high energy.

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