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The reliability of graphene-capped copper (Gr/Cu) against humidity is assessed by spectroscopic ellipsometry (SE). Changes in the volume fraction of crystalline Gr in single-layer graphene (SLG) and tri-layer graphene (TLG), and also Cu-oxide thicknesses under the Gr cap were characterized by SE before and after humidity reliability testing. It was found that TLG has a higher moisture resistance than SLG with less change in the crystalline Gr volume fraction and thickness than that of SLG, and this leads to the reduction in Cu-oxide thickness and the uniformity under the Gr cap. The results were consistent with the analysis results by X-ray photoelectron spectroscopy and Raman spectroscopy excluding variations due to differences in analysis areas of each method. Since detailed structural changes, such as Gr quality and thickness, can be evaluated non-destructively, SE is considered to be a promising method for the detailed analysis of Gr/Cu structures.

Multilayer graphene (MLG) has been proposed as an alternative material for nanometer-wide interconnects. However, it has not been put to practical use, since the process technology that leads to practical use has been immature. Recent advances in MLG processes and applications, such as MLG-capped copper interconnects, the direct deposition of MLG by solid-phase deposition (SPD) at a low temperature, stable intercalation doping to MLG and selective chemical vapor deposition (CVD) of high-crystallinity MLG for inductor and antenna applications are reviewed. Based on these advances, MLG is considered to be approaching the stage of practical application for device metallization and high-frequency devices. Based on the characteristics of MLG as a conductor and recent development trends, the prospects and issues regarding the future practical use of MLG graphene are discussed.

Doped MLG is expected as an inductor material with high inductance density due to its high kinetic inductance. A practical fabrication process for doped MLG patterns is developed using a selective CVD on Ni catalyst patterns and stable MoCl 5 intercalation. The highly doped MLG patterns of stage-2 were realized by CVD-MLG with a G/D ratio of 20 or more, and the sheet-resistance could be reduced.

We study the effect of substrate induced strain on the structural, transport, optical and electronic properties of Sr$_2$CoNbO$_6$ double perovskite thin films. The reciprocal space mapping, $\phi$-scan and high-resolution $\theta$-2$\theta$ scans of x-ray diffraction patterns suggest the epitaxial nature and high-quality of the films deposited on various single crystal ceramic substrates. A systematic enhancement in the dc electronic conductivity is observed with increase in the compressive strain, while a sharp reduction in case of tensile strain, which are further supported by change in the activation energy and density of states near the Fermi level. The optical band gap extracted from two distinct absorption bands, observed in the visible-near infrared spectroscopy show a non-monotonic behavior in case of compressive strain while significant enhancement with tensile strain. Unlike the bulk Sr$_2$CoNbO$_6$ (Co$^{3+}$ and Nb$^{5+}$), we observe different valence states of Co namely 2+, 3+ and 4+, and tetravalent Nb (4$d^1$) in the x-ray photoemission spectroscopy measurements. Moreover, a reduction in the average oxygen valency with the compressive strain due to enhancement in the covalent character of Co/Nb--O bond is evident. Interestingly, we observe sharp Raman active modes in these thin films, which indicates a significant enhancement in structural ordering as compared to the bulk., Comment: submitted

We study the structural, magnetic, transport and electronic properties of LaCoO$_3$ with Sr/Nb co-substitution, i.e., La$_{(1-2x)}$Sr$_{2x}$Co$_{(1-x)}$Nb$_{x}$O$_3$ using x-ray and neutron diffraction, dc and ac-magnetization, neutron depolarization, dc-resistivity and photoemission measurements. The powder x-ray and neutron diffraction data were fitted well with the rhombohedral crystal symmetry (space group \textit{R$\bar{3}$c}) in Rietveld refinement analysis. The calculated effective magnetic moment ($\approx$3.85~$\mu_B$) and average spin ($\approx$1.5) of Co ions from the analysis of magnetic susceptibility data are consistent with 3+ state of Co ions in intermediate-spin (IS) and high-spin (HS) states in the ratio of $\approx$50:50, i.e., spin-state of Co$^{3+}$ is preserved at least up to $x=$ 0.1 sample. Interestingly, the magnetization values were significantly increased with respect to the $x=$ 0 sample, and the M-H curves show non-saturated behavior up to an applied maximum magnetic field of $\pm$70 kOe. The ac-susceptibility data show a shift in the freezing temperature with excitation frequency and the detailed analysis confirm the slower dynamics and a non-zero value of the Vogel-Fulcher temperature T$_0$, which suggests for the cluster spin glass. The unusual magnetic behavior indicates the presence of complex magnetic interactions at low temperatures. The dc-resistivity measurements show the insulating nature in all the samples. However, relatively large density of states $\approx$10$^{22}$ eV$^{-1}$cm$^{-3}$ and low activation energy $\approx$130~meV are found in $x=$ 0.05 sample. Using x-ray photoemission spectroscopy, we study the core-level spectra of La 3$d$, Co 2$p$, Sr 3$d$, and Nb 3$d$ to confirm the valence state., Comment: submitted

The moisture barrier properties of stacked graphene layers on Cu surfaces were investigated with the goal of improving the moisture barrier efficiency of single-layer graphene (SLG) for Cu metallization. SLG with large grain size were stacked on Cu surfaces coated with CVD-SLG to cover the grain-boundaries and defective areas of the underneath SLG film, which was confirmed to be oxidized by Raman spectroscopy measurements. To evaluate the humidity resistance of the graphene-coated Cu surfaces, temperature humidity storage (THS) testing was conducted under accelerated oxidation conditions (85 °C and 85% relative humidity) for 100 h. The color changes of the Cu surfaces during THS testing were observed by optical microscopy, while the oxidized Cu into Cu2O and CuO was detected by X-ray photoelectron spectroscopy (XPS). The experimental results were accord with the results of first-principle simulation for the energetic barrier against water diffusion through the stacked graphene layers with different overlap. The results demonstrate the efficiency of SLG stacking approach against moisture for Cu metallization.

A new process using a Co-N catalyst has been developed to perform doping simultaneously with film formation in solid phase deposition method (SPD) which does not require transfer of multilayer graphene (MLG). Nitrogen doping into MLG was confirmed by XPS and UPS and succeeded in reducing sheet resistance by about 36%.

To achieve a low temperature deposition of high crystalline multilayer graphene (MLG), the effect of applying current to the catalyst layer was investigated in MLG-CVD using Ni catalyst. When the substrate temperature was varied at a fixed current, the MLG crystallinity was improved as the temperature became lower, and the G/D ratio of 40 was obtained at $464 ^{\circ}\mathrm {C}$. By optimizing the precursor flow-rate and deposition time, complete surface coverage was obtained at $490 ^{\circ}\mathrm {C}$.

In order to form a multilayer graphene film of low resistance without transferring to the device, we have developed a simultaneous doping / etching (SDE) process to remove the Ni catalyst layer during MoCl 5 intercalation doping to CVD-grown MLG on Ni catalyst. The obtained sheet resistance of the doped MLG $( \sim 20$ nm thick) was 40% lower than the MLG/Ni $( \sim 320$ nm) before the SDE process.

To improve the long-term reliability of copper (Cu) pads used in LSIs, nitrogen-doped amorphous carbon (a-C:N) coating is applied to the Cu pads with direct wire-bonding to prevent Cu oxidation in humidity. To obtain a thin barrier, the thickness optimization of a-C:N layer was carried out under temperature humidity storage (THS) testing at the conditions of 85 °C/85% relative humidity. Cu pad chains coated with the optimized a-C:N film were fabricated by direct bonding with aluminum (Al) wires. The electrical connection up to 210 bonds was obtained with the 10 and 15 nm thick a-C:N coated Cu pads. The reliability test of the pad-chains under the THS was carried out, and a 15 nm thick a-C:N can preserve the electrical connection along 100 h of the THS test. The a-C:N coating is expected to improve the humidity reliability of Cu pads with direct wire-bonding for long-term data storage.

To enhance the humidity reliability of copper (Cu) metallization used in memory LSIs, nitrogen (N)-doped amorphous carbon (a-C:N) deposited by sputtering on the Cu surface is proposed. Since the preparation of a-C:N film can be achieved at room temperature, the process temperature is compatible with LSIs fabrication. After the high-temperature/humidity storage test, the a-C:N layer was found to be an excellent barrier to protect the Cu surface from oxidation and avoid the increase of Cu sheet resistance. Depth profiles imply no oxidation occurs on the underlying Cu surface. An appropriate concentration of N-doping is considered to prevent the penetration of moisture with the effects of the repulsive force between both N and O atoms. The proposed method is promising as a practical method to improve the reliability of Cu metallization for long-term storage.

To investigate the feasibility of flash memory reliability in an environment for the application of long-term data storage, temperature and humidity acceleration tests have been carried out for commercial flash memories. Nine commercial 16GB SD cards with conventional package were kept in a test chamber of 85 °C/85%RH for up to 3040 h and we checked the write/read operation using free software "Check Flash" after the storage test. The lifetime against humidity is predicted by the power law humidity model (Peck model), which is widely used for the lifetime prediction, assuming the average parameters such as humidity acceleration factor (n) and activation energy () from the literatures. Although further studies to assure the reliability, the results indicate that commercial flash memories preliminary have the feasibility of a long-term storage media over 100 years.

Nonlinear dependence of sheet resistance change for Cu film on humidity was observed during temperature humidity storage (THS) test to evaluate the lifetime of Cu film in long-term storage in an environment. X-ray photoelectron spectroscopy (XPS) was adopted to investigate the change of oxidation structure depending on the humidity. Relative volume ratio of Cu, Cu20, and CuO was considered as the reason for the nonlinear dependence. The dominant reaction of oxidation changed from Cu20 to CuO between 75 and 85% relative humidity (RH) at 85 °C, leading to almost no reduction of Cu film thickness in spite of higher humidity.

On-chip metal inductors that revolutionized radio frequency electronics in the 1990s suffer from an inherent limitation in their scalability in state-of-the-art radio frequency integrated circuits. This is because the inductance density values for conventional metal inductors, which result from magnetic inductance alone, are limited by the laws of electromagnetic induction. Here, we report inductors made of intercalated graphene that uniquely exploit the relatively large kinetic inductance and high conductivity of the material to achieve both small form-factors and high inductance values, a combination that has proved difficult to attain so far. Our two-turn spiral inductors based on bromine-intercalated multilayer graphene exhibit a 1.5-fold higher inductance density, leading to a one-third area reduction, compared to conventional inductors, while providing undiminished Q-factors of up to 12. This purely material-enabled technique provides an attractive solution to the longstanding scaling problem of on-chip inductors and opens an unconventional path for the development of ultra-compact wireless communication systems.

The moisture barrier properties of large-grain single-layer graphene (SLG) deposited on a Cu(111)/sapphire substrate are demonstrated by comparing with the bare Cu(111) surface under an accelerated degradation test (ADT) at 85 °C and 85% relative humidity (RH) for various durations. The change in surface color and the formation of Cu oxide are investigated by optical microscopy (OM) and X-ray photoelectron spectroscopy (XPS), respectively. First-principle simulation is performed to understand the mechanisms underlying the barrier properties of SLG against O diffusion. The correlation between Cu oxide thickness and SLG quality are also analyzed by spectroscopic ellipsometry (SE) measured on a non-uniform SLG film. SLG with large grains shows high performance in preventing the Cu oxidation due to moisture during ADT.

To evaluate electromigration (EM) reliability of solder/copper (Cu) pillar bumps, a simple and lowcost test method using a flat cable has been developed. The EM lifetime of the pillar bumps with differently plated structures or different plating chemicals were compared. The results show the different lifetime distributions depending on the different structures or plating chemicals. From the results, the developed test method is considered to be effective for evaluating the EM reliability in a process development such as optimization of plating chemicals.

To improve the stability of multilayer graphene (MLG) doped with molybdenum pentachloride (MoCl 5 ) for low-resistance interconnects, we have newly developed an in-situ passivation process with molybdenum oxides. The improved air stability of dopants was confirmed with Raman spectroscopy by the direct MoO x passivation at room temperature.

To improve the crystallinity of multilayer graphene (MLG) directly deposited on SiO 2 for interconnect applications, a new solid phase precipitation (SPP) process involving current stress is investigated. It is found that the MLG crystallinity precipitated from a Cu capped Co-C layer can be improved by the vertical current to the Cu/Co-C but not by the horizontal current. The current enhanced SPP (CE-SPP) is expected as a mean to improve the MLG crystallinity directly deposited on SiO 2 .

In this paper, the results of Ge film deposited by electroplating method was studied and showed the possibility of making a NIRS sensor by the Ge film. Cu/Ti double layer structure could use the cathode electrode on the glass substrate during the GeCl4 electroplating. The deposition rate of electroplating Ge film was 100 nm/h, however, that rate was improved to 570 nm/h by introducing a spacer between Cu thin film and extraction electrode and Ar gas bubbling. The oxygen content of as-deposited film was about 10%, however, this value reduced to lower than 1% by using the Ar bubbling. The deposited film was amorphous and its optical band gap was 0.73 eV. 200 nm-thick Ge film was formed on flexible substrate by electroplating method. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

To improve crystallinity and surface morphology of multilayer graphene (MLG) films for interconnect applications, a new CVD method which introduces current stress during thermal CVD have been investigated using cobalt (Co) as the catalyst. MLG crystallinity, which is indicated by intensity ratio of G and D peaks in Raman spectra (IG/ID ratio), increased as the current was increased, and the maximum IG/ID ratios of 44 and 30 were obtained at the furnace temperature of 500 and 400 °C, respectively. Comparing with thermal CVD without direct current at the same sample temperature after taking the rising sample temperature into account due to Joule heating, higher IG/ID ratio was still led by the current enhanced CVD (CECVD) with lesser agglomeration. Besides Joule heating that may have influence in enhancing MLG growth, we assume other effects of direct current may have additional influence through grain growth of Co catalytic layer. We believe additional current in thermal CVD will lead to better control of MLG growth for interconnect applications.

To establish the lifetime prediction model for Cu-based metallization against moisture, temperature humidity storage test under the various accelerated conditions is performed. The increase of Cu sheet resistance induced by Cu-oxidation is measured by a four-point probe method. X-ray photoelectron spectroscopy analysis is carried out to investigate the variation of oxidized Cu. The activation energy and the humidity acceleration factor for Cu-based metallization have been derived by the statistical analysis to predict the lifetime against moisture for the first time. The results indicate that Cu-based metallization is comparatively more sensitive to the temperature than humidity at around the practical use condition.

Two-dimensional (2D) dose control is becoming well accepted for semiconductor device fabrication. At the same time, two specialized versions are arising; (1) High accuracy intentional non-uniform dose implant with relatively moderate dynamic dose range and (2) High dynamic dose range intentional non-uniform implant with relatively moderate dose accuracy. Sumitomo Heavy Industries Ion Technology (SMIT) has developed two-dimensional intentional non-uniform doseimplant methods for both demands. A method to carry out a high-accuracy intentional 2D non-uniform implant (MIND 2.0) will be presented at this conference. In this paper, our method to carry out a high-dynamic-range 2D non-uniform dose implant will be reported. A test implant was planned and carried out for an intentional doughnut-shape dose pattern by using the MC3-II/GP ion implanter. While the implant dose in the outmost region is neglected, we could obtain in the inner region about ten times smaller dose than in middle region in a wafer.

We have proposed a new method for in-situ doping of multiwall carbon nanotubes (MWCNTs) by catalytic CVD using nickel boron (NiB) as the catalyst. Raman spectrum measurements were carried out to determine the effects of doping using NiB catalysts with different B-concentrations at different CVD temperatures. The characteristic shifts in the Raman spectra which indicate carrier doping were demonstrated for the NiB catalyst with 18 atomic % B at the CVD temperature of 900°C. The CNT crystallinity was improved by a new catalyst structure with a B-capping layer over the NiB catalyst.

A method for producing a uniform multilayer graphene (MLG) film directly on SiO2 via solid-phase precipitation from carbon-doped cobalt (Co–C) with a Cu capping layer has been developed for a large scale integration (LSI) interconnect application. One advantage is that no transfer process is required. A 20 nm thick MLG film was grown uniformly from a 100 nm thick Co–C (20 at%) catalyst layer with a Cu capping layer. Cross-sectional TEM/EDX images revealed that the optimized Cu capping layer prevents Co agglomeration during annealing and promotes C precipitation on the SiO2 while eliminating it on the top surface of the catalytic metals.

In order to develop highly reliable Cu interconnects, temperature dependence of the electromigration (EM) lifetime of metal (CoWP) capped Cu interconnects is investigated. It is found that the EM lifetime is enhanced as the test temperature rise from 275 to 380 °C. NH3 plasma treatment before the dielectric cap layer deposition on the CoWP capped Cu interconnects influenced the temperature dependence of EM lifetime, that is, the interconnects without the NH3 plasma treatment have longer EM lifetime than those with the NH3 plasma treatment at the higher test temperatures. In order to investigate the mechanism for this lifetime enhancement, micro-analysis and failure mode analysis were carried out. It is concluded that the Co alloying with Cu and the CoWP coverage repair due to Co diffusion at the high temperature lead to the EM lifetime enhancement.

As the wiring-space decreases, the time-dependent dielectric breakdown (TDDB) of Cu/low-dielectric constant (k) interconnects becomes a critical reliability issue and more accurate prediction of the TDDB lifetime will be required. In this investigation, TDDB dependences on temperature and electric field are studied comprehensively for 90- and 65-nm-node Cu/SiOC interconnects using practical multilevel test structures with via plugs. Low-electric-field TDDB tests down to 1 MV/cm were carried out by a package TDDB method with high temperature up to 300 °C. Linear dependence of the TDDB lifetime on the electric-field is observed down to 1 MV/cm, and this suggests that the lifetime can be predicted using the E-model. The linear dependence of the TDDB lifetime on temperature is also observed up to 300 °C at 1.8 MV/cm. The activation energies for the 90 and 65 nm nodes are almost the same values, 0.76 eV for the 90 nm node and 0.74 eV for the 65 nm node. Failure is observed at the interfaces between the cap dielectric (SiCN) and the silicon dioxide layer with a surface polished by chemical-mechanical polishing (CMP) for both nodes. It is noted that no difference in the failure modes is seen between dense SiOC for the 90 nm node and porous SiOC for the 65 nm node, in spite of the different materials used for the intermetal dielectrics. This suggests that the polished interfaces greatly affect on the TDDB lifetime for both nodes. Improved TDDB lifetime is obtained by increasing the post-CMP cleaning time and the pretreatment time before the cap dielectric deposition. Sufficient TDDB lifetimes of over 10 years under practical operating conditions are obtained for both 90- and 65-nm-node Cu/low-k interconnects with via plugs.

A robust embedded ladder-oxide (k=2.9)/copper (Cu) multilevel interconnect is demonstrated for 0.13 µm complementary metal oxide semiconductor (CMOS) generation. A stable ladder-oxide intermetal dielectric (IMD) is integrated by the Cu metallization with a minimum wiring pitch of 0.34 µm, and a single damascene (S/D) Cu-plug structure is applied. An 18% reduction in wiring capacitance is obtained compared with that in SiO2 IMDs. The superior controllability of metal thickness by the S/D process enables us to enhance the MPU maximum frequency easily. The stress-migration lifetime of vias on wide metals for the S/D Cu-plug structure is longer than that for a dual damascene (D/D) structure. Reliability test results such as electromigration (EM), the temperature dependant dielectric breakdown (TDDB) of Cu interconnects, and pressure cooker test (PCT) results are acceptable. Moreover, a high flexibility in a thermal design is obtained.

To improve the crystallinity of multilayer graphene (MLG) by CVD at a low temperature, the effect of current stress during thermal CVD on a cobalt (Co) catalytic layer was investigated. The crystallinity of MLG obtained by CVD with current was higher than that without current at the same temperature. This indicates that current has effects besides the Joule heating effect. The current effects on the Co catalytic layer and the MLG growth reaction were investigated, and it was found that current had small effects on the grain size and crystal structure of the Co catalyst and large effects on the MLG growth reaction such as large grain growth and a low activation energy of 0.49 eV, which is close to the value reported for carbon surface diffusion on Co. It is considered that the enhancement of MLG growth reaction by current leads to the improved crystallinity of MLG at a relatively low temperature.

NiB and NiWB films fabricated by electroless deposition were evaluated aiming for the application to a metal cap in the copper interconnects technology. The content of B and W was varied by adjusting the concentration of components in electroless deposition baths in order to clarify the effect of co-deposited element on thermal stability of the films. The thermal stability was evaluated by Auger electron spectroscope, X-ray diffractometer (XRD) and sheet resistance measurement. By measuring the variation in sheet resistance with annealing temperature, it was confirmed that the NiB films showed good thermal stability up to 450 °C, whereas the NiWB films deteriorated at 300 °C. The effect of co-deposited element was discussed based on the results obtained by XRD as well as that of sheet resistance measurement.

In order to discuss stress-induced voiding (SIV) of Cu damascene interconnect structures in ultra-large-scale integrated circuits (ULSls), 3-D elastic-plastic finite element analysis (FEA) was carried out based on stress-temperature behavior of constituent thin films measured by a wafer curvature method. Two types of Cu interconnect geometries with either D-SiN cap/p-SiON etch-stop layers or D-SiCN : H cap/p-SiC : H etch-stop layers were analyzed. The effect of the Cu line width was also investigated. It was found from the FEA results that, regardless of the geometry, the hydrostatic tensile stress of Cu in the structure with D-SiCN : H/p-SiC : H layers was generally lower than that with p-SiN/p-SiON layers. It was also expected that, for the structure with p-SiN/p-SiON layers, SIV is most likely to occur near the via center while for the structure with p-SiCN : H/p-SiC : H layers, it is most likely to occur near the via bottom. In the structure with D-SiCN : H/p-SiC : H layers, it was considered that a larger line width is susceptible to voiding in the via due to a high hydrostatic stress gradient in the via and a high magnitude of equivalent plastic strain in the line.

Multilayer graphene (MLG)/n-GaN Schottky diodes were fabricated by transfer-free deposition of MLG on n-GaN by solid-phase reactions with cobalt as a catalyst. The thermal stability of the diodes was determined from the current–voltage (I–V) characteristics after annealing the diodes in vacuum at 200–500 °C, at intervals of 100 °C. The diode characteristics evaluated using a thermionic emission model and Cheung's function using I–V data revealed that the Schottky barrier diode (SBD) fabricated with MLG as a Schottky contact on n-GaN showed better thermal stability than the conventional Ni/n-GaN SBD. The prevention of Au diffusion to n-GaN with MLG as a diffusion barrier layer and the unaffected interface reactions between n-GaN and MLG are possible reasons for the improved thermal stability, enabling potential application of this new diode in high-power and high-temperature operations.

Transfer-free deposition of multilayer graphene (MLG) on n-GaN by a solid-phase reaction was demonstrated for the first time for the fabrication of a Schottky diode. To improve the crystallinity and uniformity of MLG films, a new approach of heat sputtering for the deposition of amorphous carbon (C) and cobalt (Co) as catalyst layers has been investigated. The characteristics obtained by Raman spectroscopy and scanning electron microscopy (SEM) measurements revealed that the crystallinity and uniformity of MLG films were improved significantly by employing heat sputtering rather than conventional room-temperature sputtering. MLG–GaN Schottky diodes were fabricated with optimized deposition of MLG on n-GaN. The Schottky barrier height determined on the basis of the thermionic emission theory using current–voltage (I–V) data was 0.75 eV. The reverse leakage current was found to be of the order of 10−7 A/mm2. The obtained results indicate the MLG fabrication on n-GaN by our proposed method might have potential applications in the fabrication of Schottky diodes.

In order to fabricate highly sensitive image sensors, ultra-high energy ion beams, such as 5 MeV of boron, are required. SEN has developed the S-UHE, a single-wafer ultra-high energy ion implanter, to obtain such ultra-high energy beams. The S-UHE has adopted an electrostatic and symmetric, parallelizing lens system, the concept of which is already used in the MC3-II, a medium-current ion implanter, and the SHX, a single-wafer high-current implanter. This system provides very good uniformity, even when a large amount of outgassing from photoresist materials is generated. Since the ion beam energy is so high at the lens system, a compound electrostatic parallelizing lens system is introduced. Beam angles have been controlled within 0.05° for any recipe in experiments with the electrostatic parallelizing lens system. Another beam line element specifically adopted in the S-UHE is an electric quadrupole lens installed between the two dipole magnets, in order to suppress beam current loss. This electric lens can easily form achromatic ion beam transportation without any significant deformation of the magnetic field.

In order to address the process requirements of leading-edge image sensors, a new single-wafer ultra-high energy ion implanter, the S-UHE, has been developed. This product incorporates two exceptional subassemblies. One is the eighteen-stage RF linear accelerator from the UHE, a multi-wafer ultra-high energy implanter, offering maximum beam energy of 2MeV per charge. The other is the field proven end station used by the MC3-II/GP, a single-wafer medium current implanter, which can provide throughput of over 450 wafers/hour. The S-UHE has a unique beam line concept where beam energy analyzing magnets bend the accelerated beam 180°. This system minimizes tool footprint, providing additional space for maintenance. Other key elements of the beam line include an electrostatic scanner, parallelizing lens and energy filter. The electrostatic scanner provides higher scan speed than mechanical systems - significantly improving dose uniformity compared to a batch high energy implanter. Additionally, the S-UHE ensures accurate implant angles and ultra-low level of metal contamination, both of which are very important parameters for advanced image sensors.

In order to fabricate highly sensitive image sensors (IS), ultra-high energetic ion beams such as 5MeV of boron are required. In order to address the requirement as well as more aggressive requirements of leading-edge IS, SEN has developed the S-UHE, an ultra-high energy single-wafer ion implanter. One of the most important features in the S-UHE is a precise beam angle control system to obtain stable implant depth of ion species against angle-sensitive channeling effects. It is very important for the precise control both to design a sophisticated beam line and to measure beam angles accurately. In this report, measuring techniques of the beam angle and the results are presented.

Objective/Methods: Long-term administration of clarithromycin has been reported to be effective in the treatment of chronic sinusitis. To investigate the mechanism underlying the anti-inflammatory activity of clarithromycin, the authors evaluated the effect of clarithromycin on the gene expression of proinflammatory cytokine and the DNA-binding activity of nuclear factor (NF)-κB in cultured human nasal epithelial cells and fibroblasts. Cells were incubated with endotoxin purified from nontypeable Haemophilus influenzae or interleukin (IL)-1β in the presence of clarithromycin. Results: Northern blot analysis revealed that clarithromycin suppressed IL-1β gene expression in human nasal epithelial cells stimulated by H influenzae endotoxin (HIE). Intercellular adhesion molecule-1 gene expression in nasal fibroblasts stimulated by IL-1β was also suppressed by clarithromycin. Furthermore, electrophoretic mobility shift assay demonstrated that clarithromycin reduced DNA-binding activity of NF-κB in both human nasal epithelial cells and fibroblasts stimulated by HIE or IL-1β, respectively. Conclusion: The present results suggest that clarithromycin may reduce gene expression of proinflammatory cytokines and adhesion molecules from nasal mucosa at the transcriptional factor level and exert an anti-inflammatory effect on nasal mucosa in chronic sinusitis.

Room-temperature recrystallization (self-annealing) of electroplated copper (Cu) films is investigated using three kinds of seed/barrier layers with nontexture and (111) texture. The as-plated films have almost the same texture as the seeds. The texture changes during self-annealing depend on the seed texture. The (111) texture of the self-annealing films increases for the film deposited on the nontexture seed layer, but decreases for the film deposited on (111) texture seed layers. For all the plated films, tensile stress increases after self-annealing, which corresponds to the film shrinkage. Recrystallization rate of the Cu film plated on the nontexture seed layer is higher than the one on the (111) texture seed. It is postulated that the reduction of grain boundary energy is the major driving force for film self-annealing and grain growth.