Ar Cluster Ion Bombardment Effects on Semiconductor Surfaces

2000 ◽  
Vol 647 ◽  
Author(s):  
Toshio Seki ◽  
Kazumichi Tsumura ◽  
Takaaki Aoki ◽  
Jiro Matsuo ◽  
Gikan H. Takaoka ◽  
...  
Keyword(s):  
Surface Modification ◽  
Variable Temperature ◽  
Ion Beam ◽  
High Vacuum ◽  
Ion Bombardment ◽  
Ultra High Vacuum ◽  
Scanning Tunneling ◽  
Cluster Ion ◽  
Ion Impact ◽  
The Impact

AbstractNew surface modification processes have been demonstrated using gas cluster ion irradiations because of their unique interaction between cluster ions and surface atoms. For example, high quality ITO films could be obtained by O2 cluster ion assisted deposition at room temperature. It is necessary to understand the role of cluster ion bombardment during film formation for the further developments of this technology. Variable Temperature Scanning Tunneling Microscope (VT-STM) in Ultra High Vacuum (UHV) allows us to study ion bombardment effects on surfaces and nucleation growth at various temperatures.The irradiation effects between Ar cluster ion and Xe monomer ion were compared. When a Si(111) surface with Ge deposited to a few Å was annealed to 400°C, it was observed that many islands of Ge were formed. The surface with the Ge islands was irradiated by these ions. In the STM image of cluster-irradiated surface, large craters with diameter of about 100 Å were observed, while only small traces with diameter of about 20 Å were observed in monomer-irradiated surface. The number of Ge atoms displaced by one Ar cluster ion impact was much larger than that by one Xe ion impact. This result indicates that Ar cluster ion impacts can enhance the physical modification of Ge islands. When the sample irradiated with Ar cluster was annealed at 600°C, the hole remained, but the outer rim of the crater disappeared and the surface structure was reconstructed at the site of the rim. The depth of damage region in the target became shallower with decrease of the impact energy. These results indicate that low damage and useful surface modification can be realized using the cluster ion beam.

Size Dependence of Bombardment Characteristics Produced by Cluster Ion Beams

1997 ◽  
Vol 504 ◽  
Author(s):  
T. Seki ◽  
M. Tanomura ◽  
T. Aoki ◽  
J. Matsuo ◽  
I. Yamada
Keyword(s):  
Ion Beam ◽  
Local Area ◽  
Carbon Cluster ◽  
High Rate ◽  
Cluster Ions ◽  
Scanning Tunneling ◽  
Cluster Ion Beams ◽  
Cluster Ion ◽  
Ion Impact ◽  
The Impact

ABSTRACTCluster ion beam processes provide new surface modification techniques, such as surface smoothing, high rate sputtering and very shallow implantation, because of the unique interactions between cluster and surface atoms. To understand interactions with cluster and surface, Scanning Tunneling Microscope (STM) observations have been done for single impact traces.Highly Oriented Pyrolitic Graphite (HOPG) surfaces were bombarded by carbon cluster ions (Va≤300kV), and large ridges and craters have been observed as a result of single cluster ion impact. The impact site diameters are proportional to the cluster size up to 10 atoms, and increase drastically for cluster sizes above 10. This indicates that non-linear multiple collisions occur only when a local area is bombarded by more than 10 atoms at the same time.

scholarly journals Navigate flying molecular elephants safely to the ground: mass-selective soft landing up to the Mega-Dalton range by Electrospray Controlled Ion-Beam Deposition

2021 ◽  
Author(s):  
Andreas Walz ◽  
Karolina Stoiber ◽  
Annette Huettig ◽  
Hartmut Schlichting ◽  
Johannes V Barth
Keyword(s):  
Ion Beam ◽  
High Vacuum ◽  
Mass Range ◽  
Ultra High Vacuum ◽  
Scanning Tunneling ◽  
Soft Landing ◽  
Ion Beam Deposition ◽  
Maximum Resolution ◽  
Ion Guides ◽  
Beam Deposition

The prototype of a highly versatile and efficient preparative mass spectrometry system used for the deposition of molecules in ultra-high vacuum (UHV) is presented, along with encouraging performance data obtained on four model species which are thermolabile or not sublimable. The test panel comprises two small organic compounds, a protein, and a large DNA species covering a 4-log mass range up to 1.7 MDa as part of a broad spectrum of analyte species evaluated to date. Three designs of innovative ion guides, a novel digital mass-selective quadrupole (dQMS) and a standard electrospray ionization (ESI) source are combined to an integrated device, abbreviated Electrospray Controlled Ion Beam Deposition (ES-CIBD). Full control is achieved by i) the square-wave-driven radiofrequency (RF) ion guides with steadily tunable frequencies, including a dQMS allowing for investigation, purification and deposition of a virtually unlimited m/z range, ii) the adjustable landing energy of ions down to ~2 eV/z enabling integrity-preserving soft-landing, iii) the deposition in UHV with high ion beam intensity (up to 3 nA) limiting contaminations and deposition time, and iv) direct coverage control via the deposited charge. The maximum resolution of R=650 and overall efficiency up to T_total=4.4% calculated from solution to UHV deposition are remarkable as well, while the latter is mainly limited by the not yet optimized ionization performance. In the setup presented, a scanning tunneling microscope (STM) is attached for in situ UHV investigation of the deponents demonstrating a selective, structure-preserving process and atomically clean layers.

Ultra high vacuum compatible metal ion beam surface modification system

1990 ◽  
Vol 61 (11) ◽  
pp. 3412-3415
Author(s):  
Yuzo Mori ◽  
Hui Wang ◽  
Katsuyoshi Endo ◽  
Kazuto Yamauchi ◽  
Takashi Ide ◽  
...  
Keyword(s):  
Surface Modification ◽  
Metal Ion ◽  
Ion Beam ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Modification System ◽  
Beam Surface

Ultra Shallow Junction Formation by Cluster Ion Implantation

1998 ◽  
Vol 532 ◽  
Author(s):  
Jiro Matsuo ◽  
Takaaki Aoki ◽  
Ken-ichi Goto ◽  
Toshihiro Sugii ◽  
Isao Yamada
Keyword(s):  
Depth Distribution ◽  
Ion Beam ◽  
Beam Current ◽  
Cluster Ions ◽  
Junction Depth ◽  
Junction Formation ◽  
Order Of Magnitude ◽  
Cluster Ion ◽  
Ion Impact ◽  
The Impact

ABSTRACTImplantation of B cluster ions into Si using decaborane (B10H14) has been demonstrated. SIMS measurements show that the depth distribution of boron atoms implanted with a monomer ion is exactly matched by that of boron atoms implanted from decaborane ions, if the cluster ion has an order of magnitude larger acceleration energy. According to the Langmuir-Child equation, two orders of magnitude larger space-charge limited ion beam current is possible when decaborane ions are used. Implanted boron atoms from decaborane ions are electrically activated after annealing. Junction depth of the implanted layer with 3 keV decaborane ions is approximately 20nm after annealing at 900°C. Molecular dynamic caluculations show that implantation efficency of boron monomer ions and decaborane ions are the same. However, the number of displaced silicon atoms per implanted boron atom from a decaborane ion impact is 4 times larger than that by boron monomer impact so that a heavily damaged region is created near the impact zone by decaborane ion penetration.

scholarly journals Navigate flying molecular elephants safely to the ground: mass-selective soft landing up to the Mega-Dalton range by Electrospray Controlled Ion-Beam Deposition

2021 ◽  
Author(s):  
Andreas Walz ◽  
Karolina Stoiber ◽  
Annette Huettig ◽  
Hartmut Schlichting ◽  
Johannes V Barth
Keyword(s):  
Ion Beam ◽  
High Vacuum ◽  
Mass Range ◽  
Ultra High Vacuum ◽  
Scanning Tunneling ◽  
Soft Landing ◽  
Ion Beam Deposition ◽  
Maximum Resolution ◽  
Ion Guides ◽  
Beam Deposition

The prototype of a highly versatile and efficient preparative mass spectrometry system used for the deposition of molecules in ultra-high vacuum (UHV) is presented along with encouraging performance data obtained on model species which are thermolabile or not sublimable. The test panel comprises two organic compounds, a protein, and DNA covering a 4-log mass range up to 1.7 MDa as part of a broad spectrum of analyte species. Three designs of innovative ion guides, a novel digital mass-selective quadrupole (dQMS) and a standard electrospray ionization (ESI) source are combined to an integrated device, abbreviated Electrospray Controlled Ion Beam Deposition (ES-CIBD). Full control is achieved by i) the square-wave-driven radiofrequency (RF) ion guides with steadily tunable frequencies, including a dQMS allowing for investigation, purification and deposition of a virtually unlimited m/z range, ii) the adjustable landing energy of ions down to ~2 eV/z enabling integrity-preserving soft-landing, iii) the deposition in UHV with high ion beam intensity (up to 3 nA) limiting contaminations and deposition time, and iv) direct coverage control via the deposited charge. The maximum resolution of R=650 and overall efficiency up to T-total=4.4% calculated from solution to UHV deposition are remarkable as well, while the latter is mainly limited by the not yet optimized ionization performance. In the setup presented, a scanning tunneling microscope (STM) is attached for in situ UHV investigation of the deponents demonstrating a selective, structure-preserving process and atomically clean layers.

scholarly journals Effects of surface treatments on flux tunable transmon qubits

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
M. Mergenthaler ◽  
C. Müller ◽  
M. Ganzhorn ◽  
S. Paredes ◽  
P. Müller ◽  
...  
Keyword(s):  
Fault Tolerant ◽  
Ion Irradiation ◽  
Uv Light ◽  
Light Exposure ◽  
High Vacuum ◽  
Ion Bombardment ◽  
Ultra High Vacuum ◽  
Sweet Spot ◽  
Noise Sources ◽  
The Impact

AbstractOne of the main limitations in state-of-the art solid-state quantum processors is qubit decoherence and relaxation due to noise from adsorbates on surfaces, impurities at interfaces, and material defects. For the field to advance towards full fault-tolerant quantum computing, a better understanding of these microscopic noise sources is therefore needed. Here, we use an ultra-high vacuum package to study the impact of vacuum loading, UV-light exposure, and ion irradiation treatments on relaxation and coherence times, as well as slow parameter fluctuations of flux tunable superconducting transmon qubits. The treatments studied do not significantly impact the relaxation rate Γ1 and the echo decay rate $${{{\Gamma }}}_{2,{{{\rm{SS}}}}}^{{{{\rm{e}}}}}$$ Γ 2 , SS e at the sweet spot, except for Ne ion bombardment which reduces Γ1. In contrast, flux noise parameters are improved by removing magnetic adsorbates from the chip surfaces with UV-light and NH3 treatments. Additionally, we demonstrate that SF6 ion bombardment can be used to adjust qubit frequencies in situ and post-fabrication without affecting qubit relaxation and coherence times at the sweet spot.

scholarly journals Strain-Relief Patterns and Kagome Lattice in Self-Assembled C60 Thin Films Grown on Cd(0001)

2021 ◽  
Vol 22 (13) ◽  
pp. 6880
Author(s):  
Zilong Wang ◽  
Minlong Tao ◽  
Daxiao Yang ◽  
Zuo Li ◽  
Mingxia Shi ◽  
...  
Keyword(s):  
Thin Films ◽  
Self Assembly ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Scanning Tunneling ◽  
Kagome Lattice ◽  
Tunneling Microscopy ◽  
Kagomé Lattice ◽  
Temperature Scanning ◽  
C60 Films

We report an ultra-high vacuum low-temperature scanning tunneling microscopy (STM) study of the C60 monolayer grown on Cd(0001). Individual C60 molecules adsorbed on Cd(0001) may exhibit a bright or dim contrast in STM images. When deposited at low temperatures close to 100 K, C60 thin films present a curved structure to release strain due to dominant molecule–substrate interactions. Moreover, edge dislocation appears when two different wavy structures encounter each other, which has seldomly been observed in molecular self-assembly. When growth temperature rose, we found two forms of symmetric kagome lattice superstructures, 2 × 2 and 4 × 4, at room temperature (RT) and 310 K, respectively. The results provide new insight into the growth behavior of C60 films.

scholarly journals Au(100) as a Template for Pentacene Monolayer

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2393
Author(s):  
Artur Trembułowicz ◽  
Agata Sabik ◽  
Miłosz Grodzicki
Keyword(s):  
Self Assembly ◽  
Molecular Layer ◽  
High Vacuum ◽  
Gold Surface ◽  
Ultra High Vacuum ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Height Difference ◽  
Characteristic Features ◽  
Reconstructed Surface

The surface of quasi-hexagonal reconstructed Au(100) is used as the template for monolayer pentacene (PEN) self-assembly. The system is characterized by means of scanning tunneling microscopy at room temperature and under an ultra-high vacuum. A new modulated pattern of molecules with long molecular axes (MA) arranged along hex stripes is found. The characteristic features of the hex reconstruction are preserved herein. The assembly with MA across the hex rows leads to an unmodulated structure, where the molecular layer does not recreate the buckled hex phase. The presence of the molecules partly lifts the reconstruction—i.e., the gold hex phase is transformed into a (1×1) phase. The arrangement of PEN on the gold (1×1) structure is the same as that of the surrounding molecular domain on the reconstructed surface. The apparent height difference between phases allows for the distinction of the state of the underlying gold surface.

Carbon Nitride Film Formation by Low Energy Positive and Negative Ion Beam Deposition

1996 ◽  
Vol 438 ◽  
Author(s):  
N. Tsubouchi ◽  
Y. Horino ◽  
B. Enders ◽  
A. Chayahara ◽  
A. Kinomura ◽  
...  
Keyword(s):  
Carbon Nitride ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
High Vacuum ◽  
Negative Ions ◽  
Low Energy ◽  
Ultra High Vacuum ◽  
Negative Ion ◽  
Nitride Film ◽  
Ion Energy

AbstractUsing a newly developed ion beam apparatus, PANDA (Positive And Negative ions Deposition Apparatus), carbon nitride films were prepared by simultaneous deposition of mass-analyzed low energy positive and negative ions such as C2-, N+, under ultra high vacuum conditions, in the order of 10−6 Pa on silicon wafer. The ion energy was varied from 50 to 400 eV. The film properties as a function of their beam energy were evaluated by Rutherford Backscattering Spectrometry (RBS), Fourier Transform Infrared spectroscopy (FTIR) and Raman scattering. From the results, it is suggested that the C-N triple bond contents in films depends on nitrogen ion energy.

Sign in / Sign up

Export Citation Format

Share Document