Electron Cyclotron Resonance Sputtering Research Articles

(Invited) Fabrication and Characterization of Ge-Based MIS Structures

Germanium (Ge) is a very attractive channel material for future high-performance metal-insulator-semiconductor (MIS) devices because it exhibits much higher low-field electron (two times higher) and hole (four times higher) mobilities than Si. In addition, the smaller band gap of Ge than that of Si should allow the further reduction of power consumption in advanced integrated circuits and the lower melting point of Ge than that of Si also enables Ge-based device integration at low processing temperatures. However, until the early years of the 2000s, the reported electrical properties of high-k/Ge interfaces had been so poor that one of the critical issues in establishing Ge-based MIS technology was the effective passivation of Ge surfaces by dielectrics with superior interface properties. Although the quality of the Ge-MIS structure has been remarkably improved in the past decade, the relationship between the processing methods and the quality has not been discussed precisely.In this paper, we report on the fabrication of Ge MIS structures with various high-k dielectric materials and interlayer materials through various methods. We also introduce the convenient method to characterize the interface trap densities (Dit's) of the MIS capacitors by spectroscopic measurement of the interface trap density in an insulator/Ge interface at room temperature [1]. The effects of the insertion of interlayers into the interface of high-k insulator/Ge and the application of heat treatment to the Ge MIS structures will be also presented.For instance, the Dit of Ta2O5/GeNx/Ge fabricated by electron-cyclotron-resonance (ECR) plasma nitridation and sputtering was estimated to be 4×1011 cm-2 · eV-1 [2], that of Si3N4/GeNx/Ge by ECR plasma nitridation to be 1×1011 cm-2 · eV-1 [3-6], and that of Al2O3/GeO2/Ge by ECR plasma oxidation and sputtering to be 4.5×1010 cm-2 · eV-1 [7-9]. These results have summarized that the adequate surface preparations of the interfaces and films by the ECR plasma process with low energy plasma irradiation have been effective to realize the low Dit of MIS structures with GeO2 and/or GeNx.These results have expanded to another MIS structures fabricated by more conventional film formation technique such as the atomic layer deposition (ALD) and the radio frequency (RF) magnetron sputtering. The Dit of Al2O3/Al germanate/Ge by ALD with trimethylaluminum (TMA) and microwave-generated atomic oxygen was estimated to be 2×1011cm-2 · eV-1 [10], and that of HfO2/Ge by RF magnetron sputtering to be 5.9×1011 cm-2 · eV-1. These results have summarized that the heat treatment after the fabrication of MIS strucures have affected interface properties of germanate/Ge and oxide/Ge.Although the mechanism by which the process conditions act on the interface state is now under estimation, it has been speculated that the fabrication method, the insertion of the interlayers, and the application of heat treatment have a great influence on the interface characteristics. The structures and the fabrication method of various MIS will be discussed.Part of this work was carried out under the Cooperative Research Project Program of the Research Institute of Electrical Communication, Tohoku University.

Superhydrophobic, photo-sterilize, and reusable mask based on graphene nanosheet-embedded carbon (GNEC) film.

The 2019 coronavirus disease (COVID-19) has affected more than 200 countries. Wearing masks can effectively cut off the virus spreading route since the coronavirus is mainly spreading by respiratory droplets. However, the common surgical masks cannot be reused, resulting in the increasing economic and resource consumption around the world. Herein, we report a superhydrophobic, photo-sterilize, and reusable mask based on graphene nanosheet-embedded carbon (GNEC) film, with high-density edges of standing structured graphene nanosheets. The GNEC mask exhibits an excellent hydrophobic ability (water contact angle: 157.9°) and an outstanding filtration efficiency with 100% bacterial filtration efficiency (BFE). In addition, the GNEC mask shows the prominent photo-sterilize performance, heating up to 110 °C quickly under the solar illumination. These high performances may facilitate the combat against the COVID-19 outbreaks, while the reusable masks help reducing the economic and resource consumption.Electronic Supplementary MaterialSupplementary material (further details of electron cyclotron resonance (ECR) sputtering system, deposition of GNEC film, fabrication of GNEC mask, and characterization of the GNEC mask) is available in the online version of this article at 10.1007/s12274-020-3158-1.

Study of a reversible resistive switching mechanism in bismuth titanate deposited by electron cyclotron resonance sputtering

We studied the temperature dependence of the reversible resistance switching in the bismuth titanate (BiTiO) film deposited by electron cyclotron resonance sputtering. The reversible resistance switching was observed at 5 K in both the low resistance state (LRS) and high resistance state (HRS) in the film. The resistance in the LRS decreased with increasing temperature, and remained unchanged regardless of an electrode-pad area. On the other hand, the resistance in the HRS increased with temperature, exhibiting the electrode-pad area dependence. From the cross-sectional transmission electron microscope image, nanocrystalline Bi4Ti3O12 particles were uniformly distributed in the BiTiO film. We proposed the mechanism of reversible resistance switching in BiTiO, that is, (1) the filament of conduction path was generated along the grain boundaries of the nanocrystalline particles by electroforming, (2) the LRS was switched-on, and (3) the filament was cut off by applying reverse bias voltages, switching back to the HRS. We verified the conduction of three-dimensional variable range hopping in the HRS.

Bias-Modulated High Photoelectric Response of Graphene-Nanocrystallite Embedded Carbon Film Coated on n-Silicon.

We propose that bias-modulated graphene-nanocrystallites (GNs) grown vertically can enhance the photoelectric property of carbon film coated on n-Si substrate. In this work, GN-embedded carbon (GNEC) films were deposited by the electron cyclotron resonance (ECR) sputtering technique. Under a reverse diode bias which lifts the Dirac point of GNs to a higher value, the GNEC film/n-Si device achieved a high photocurrent responsivity of 0.35 A/W. The bias-modulated position of the Dirac point resulted in a tunable ON/OFF ratio and a variable spectral response peak. Moreover, due to the standing structured GNs keeping the transport channels, a response time of 2.2 μs was achieved. This work sheds light on the bias-control wavelength-sensitive photodetector applications.

Nanocrystalline/amorphous biphase enhanced mechanical properties in multilayer carbon films

This study reports the nanostructure evolution and mechanical properties improvement in the nanocrystalline/amorphous multilayer carbon films. Electron cyclotron resonance sputtering and electron/ion alternative irradiation techniques were used to deposit the multilayer carbon films with the total film thicknesses ranging from 130 to 10nm and the single layer thicknesses ranging from 4 to 1nm. The high resolution transmission electron microscopy observation showed that the interface between nanocrystalline layer and amorphous layer evolved from an original toothed structure to a mixed biphase structure, and the nanocrystallite size in nanocrystalline layer decreased when layer thickness was reduced from 4 to 1nm. The nano-indenter tests showed a significant improvement in hardness of multilayer film when single layer thickness was reduced from 4 to 1nm. The scratch tests revealed that good scratch resistance could be preserved in the multilayer film with 1nm single layer thickness when total film thickness was only 10nm. This work may shed light on the ultrathin multilayered coating technology.

ECR sputtering and electron/ion alternative irradiation for multilayer carbon films fabrication with tunable layer thickness

Abstract In this work, we proposed a method of electron cyclotron resonance (ECR) sputtering and electron/ion alternative irradiation to form multilayer carbon films with different single layer thicknesses. The soft electron irradiated layers and protective ion irradiated layers were deposited as the component layers. The transmission electron microscopy (TEM) and Raman spectra proved that the graphene sheets structure in electron irradiated layers could be preserved in multilayer carbon films. We found a rule of the dependence of the surface roughness, mechanical and tribological properties of the multilayer films on the single layer thickness. With the decrease of single layer thickness, the surface roughness decreased and the mechanical and tribological properties improved notably. The mechanisms of the long wear life with low friction coefficient were further discussed based on the hardness enhancement and the cracking length limitation. This work indicated that by decreasing the single layer thickness, ECR sputtering and electron/ion alternative irradiation can fabricate films with combined properties of the component materials, which can be expected for broad nanolayered surface science and engineering applications.

Three-layered sandwich structured carbon film prepared by sputtering and ion/electron/ion alternative irradiation

The electron irradiated carbon film based on electron cyclotron resonance (ECR) sputtering technology has been proved to have both high conductivity and paramagnetism. However, the relatively low hardness, wear life and high surface roughness value limit its application in Micro-electromechanical Systems (MEMS). To improve these properties, the sandwich structured carbon films with different modulation ratios were introduced on silicon (100) wafers by alternative irradiation (ion/electron/ion) technique in ECR sputtering system. The three-layered nanostructure of films was measured with a transmission electron microscopy (TEM). The surface roughness of the film can be controlled to 0.19nm according to the measurement of atomic force microscope (AFM). The unique characteristics of electron irradiated layer remained stable after irradiation through the analyzing of Raman spectroscopy. The mechanical properties (including hardness, elastic modulus, fracture behavior) and wear life were improved significantly due to the sandwich structure. The results showed that the sandwich structured carbon film is a kind of functional material equipped with enhanced mechanical and tribological properties.

Development of a sputter-deposited nanocarbon thin film electrode for use as a biosensor

We have developed nanocarbon film electrodes formed by an electron cyclotron resonance (ECR) sputtering method. The nanocarbon film contains a nano-crystalline sp2 and sp3 mixed bond structure with an atomically flat surface and has a wide potential window, relatively high electrochemical activity and a low background noise level similar to a boron-doped diamond electrode. Surface conditions such as hydrophilicity on the nanocarbon film electrode can be controlled by electrochemical treatments while maintaining the wide potential window and surface flatness, and, therefore, in measurements of various biomolecules including oxidatively damaged DNA and oligonucleotides, their adsorption onto the electrode surface is suppressed. For example, cytosine and methylated cytosine in oligonucleotides can be distinguished by square wave voltammetry. A carbon electrode with a thorn-like nanostructure could be fabricated by UV/ozone treatment using different etching rates depending on nanometer-order differences in the local sp3 content of the nanocarbon film. This nanostructured surface was very effective in improving efficient direct electron transfer (DET) with enzymes such as bilirubin oxidase. Carbon film electrodes doped with metal nanoparticles have been also developed by co-sputtering metal and carbon. A Pt-nanoparticle-dispersed carbon electrode shows high electrochemical activity and stability for detecting hydrogen peroxide indicating that it is suitable for use as a biosensor. [TANSO 2014 (No. 264), 133–9.]

Structure and electrochemical characterization of carbon films formed by unbalanced magnetron (UBM) sputtering method

We previously reported nanocarbon films formed by the electron cyclotron resonance (ECR) sputtering method. The films contain a nanocrystalline structure consisting of sp3 and sp2 bonds with an extremely flat surface (Ra=0.07nm). The film also has a wider potential window than glassy carbon and superior electrochemical activity to boron doped diamond for certain species. However, ECR sputtering equipment is much more expensive than that used for conventional sputtering and requires a ring-shaped target. Therefore, it is difficult to use this method to develop new electrode materials such as metal-carbon hybrid film. Here, we describe a nanocarbon film electrode that we developed with a potential window and electrochemical activity equivalent to those of ECR nanocarbon films by using unbalanced magnetron (UBM) sputtering equipment. Our approach uses conventional equipment and has widely controllable sputtering conditions including a high sputtering rate, a large sputtering area and the capacity for co-sputtering multiple materials. The film can contain a maximum of 53% sp3 bonds by increasing the substrate bias voltage between the target and substrate, and also exhibits a potential window equivalent to that of the ECR nanocarbon film. However, the electrode surface is about one order of magnitude rougher than that of the ECR nanocarbon film due to the effect of reflected Ar+ ions caused by the fact that the target surface is facing the substrate surface. By employing transmission electron microscopy, we could observe nanocrystalline graphene structures in the UBM nanocarbon film, which are difficult to observe in conventional diamond-like carbon film. The electron transfer rate at the UBM nanocarbon film is similar to those of ECR nanocarbon film for Ru(NH3)63+ and Fe(CN)64−, suggesting that the nanocrystalline structure could contribute to a relatively fast electron transfer rate. The UBM nanocarbon films were successfully used for detecting kynurenic acid, which has a high oxidation potential and is difficult to detect with a conventional glassy carbon electrode.

Correction to Structure and Electrochemical Performance of Nitrogen-Doped Carbon Film Formed by Electron Cyclotron Resonance Sputtering

ADVERTISEMENT RETURN TO ISSUEPREVAddition/CorrectionORIGINAL ARTICLEThis notice is a correctionCorrection to Structure and Electrochemical Performance of Nitrogen-Doped Carbon Film Formed by Electron Cyclotron Resonance SputteringTomoyuki Kamata, Dai Kato, Shigeru Hirono, and Osamu Niwa*Cite this: Anal. Chem. 2014, 86, 3, 1925Publication Date (Web):January 22, 2014Publication History Published online22 January 2014Published inissue 4 February 2014https://doi.org/10.1021/ac404138hCopyright © 2014 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views301Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (102 KB) Get e-Alerts Get e-Alerts

バイオセンサ応用を目的としたスパッタナノカーボン薄膜電極の開発

We have developed nanocarbon film electrodes formed by an electron cyclotron resonance (ECR) sputtering method. The nanocarbon film contains a nano-crystalline sp2 and sp3 mixed bond structure with an atomically flat surface and has a wide potential window, relatively high electrochemical activity and a low background noise level similar to a boron-doped diamond electrode. Surface conditions such as hydrophilicity on the nanocarbon film electrode can be controlled by electrochemical treatments while maintaining the wide potential window and surface flatness, and, therefore, in measurements of various biomolecules including oxidatively damaged DNA and oligonucleotides, their adsorption onto the electrode surface is suppressed. For example, cytosine and methylated cytosine in oligonucleotides can be distinguished by square wave voltammetry. A carbon electrode with a thorn-like nanostructure could be fabricated by UV/ozone treatment using different etching rates depending on nanometer-order differences in the local sp3 content of the nanocarbon film. This nanostructured surface was very effective in improving efficient direct electron transfer (DET) with enzymes such as bilirubin oxidase. Carbon film electrodes doped with metal nanoparticles have been also developed by co-sputtering metal and carbon. A Pt-nanoparticle-dispersed carbon electrode shows high electrochemical activity and stability for detecting hydrogen peroxide indicating that it is suitable for use as a biosensor.

Structure and Electrochemical Performance of Nitrogen-Doped Carbon Film Formed by Electron Cyclotron Resonance Sputtering

A nitrogen-doped nanocarbon film electrode with mixed sp(2) and sp(3) bonds formed using the electron cyclotron resonance (ECR) sputtering method was studied with respect to the relationship between nitrogen concentration and electrochemical performance. The film (N-ECR) has a nanocrystalline structure, and the sp(3) content increases with increasing nitrogen concentration unlike the recently reported nitrogen-containing tetrahedral amorphous carbon film.1 The film has a very smooth surface with an average roughness of 0.1 to 0.2 nm, which is almost independent of nitrogen concentration. In contrast, the ratio of nitrogen-containing graphite-like bonding is high at low nitrogen concentrations, and then pyridine-like bonding increases as the nitrogen concentration increases. These variations in the chemical structures and the sp(2) and sp(3) content greatly change the electrochemical performance. The N-ECR electrode shows a wider potential window (∼3.8 V) than a pure nanocarbon electrode (∼3.1 V) due to its higher sp(3) content. The N-ECR electrode (N = 9.0 at. %) shows improved electrochemical activity because the lowest peak separation of Fe(CN)6(3-/4-) was observed at this nitrogen concentration. The oxygen and hydrogen peroxide (H2O2) reduction potentials at the N-ECR electrode shifted about 0.3 and 0.15 V, respectively, and the peak height of H2O2 is greatly increased. As a result, a linear relationship was obtained from 0.2 to 17 mM for the reductive current detection of H2O2. The N-ECR electrode also shows better activity for oxidizing certain biomolecules. The oxidation potentials of guanosine and adenosine decreased about 0.1 V, suggesting that the N-ECR electrode is suitable for use as a biosensing platform.

An artificial fusion protein between bone morphogenetic protein 2 and titanium‐binding peptide is functional in vivo

The purpose of this study was to investigate osteogenesis using an artificial fusion protein (AFP) composed of modified bone morphogenetic protein 2 (BMP-2) with a titanium (Ti)-binding peptide (TBP) motif on a Ti surface in vivo. In the in vivostudy, 5-μm thick Ti was coated with electron cyclotron resonance sputtering on a porous carbon scaffold which was then dipped in one of three different mixtures of collagen gel: (1) collagen gel only, (2) collagen gel with TBP, and (3) collagen gel with the AFP between BMP-2 and the TBP motif (AFP-TBP-BMP-2). These scaffolds were then implanted into rat abdominal muscles and were studied histologically at various times and the expression of several bone-related protein messenger RNAs (mRNAs) was also analyzed. The Ti-coated scaffold of the collagen gel with AFP-TBP-BMP-2 produced cartilage in the muscle and the expression of alkaline phosphatase, bone sialoprotein, and runt-related gene 2 mRNAs was significantly increased. These results suggest that the scaffold of the collagen gel with AFP-TBP-BMP-2 accelerates osteogenesis in vivo.

Surface modification of amorphous carbon thin films by 1,3-dipolar cycloaddition

Amorphous carbon thin film surfaces were successfully modified by 1,3-dipolar cycloaddition of nitrones, generated by the condensation of 4-(trifluoromethyl)benzaldehyde and N-methylhydroxylamine. Amorphous carbon thin films were deposited by electron cyclotron resonance sputtering and consisted of mainly sp2-hybridized carbon. The modification of amorphous carbon thin film surfaces with organic molecules was confirmed by X-ray photoelectron spectroscopy (XPS), Raman, and atomic force microscopy (AFM). F 1s, N 1s, and C 1s electron spectra revealed the existence of organic molecules on the surface of modified amorphous carbon thin films. The surface coverage increased with reaction temperature, reactant concentration, and reaction time.

Evaluation of Electrokinetic Parameters for All DNA Bases with Sputter Deposited Nanocarbon Film Electrode

The electrokinetic parameters of all the DNA bases were evaluated using a sputter-deposited nanocarbon film electrode. It is very difficult to evaluate the electrokinetic parameters of DNA bases with conventional electrodes, and particularly those of pyrimidine bases, owing to their high oxidation potentials. Nanocarbon film formed by employing an electron cyclotron resonance sputtering method consists of a nanocrystalline sp(2) and sp(3) mixed bond structure that exhibits a sufficient potential window, very low adsorption of DNA molecules, and sufficient electrochemical activity to oxidize all DNA bases. A precise evaluation of rate constants (k) between all the bases and the electrodes is achieved for the first time by obtaining rotating disc electrode measurements with our nanocarbon film electrode. We found that the k value of each DNA base was dominantly dependent on the surface oxygen-containing group of the nanocarbon film electrode, which was controlled by electrochemical pretreatment. In fact, the treated electrode exhibited optimum k values for all the mononucleotides, namely, 2.0 × 10(-2), 2.5 × 10(-1), 2.6 × 10(-3), and 5.6 × 10(-3) cm s(-1) for GMP, AMP, TMP, and CMP, respectively. The k value of AMP was sufficiently enhanced by up to 33 times with electrochemical pretreatment. We also found the k values for pyrimidine bases to be much lower than those of purine bases although there was no large difference between their diffusion coefficient constants. Moreover, the theoretical oxidation potential values for all the bases coincided with those obtained in electrochemical experiments using our nanocarbon film electrode.

Microstructure and piezoelectric properties of AlN thin films grown on stainless steel for the application of vibration energy harvesting

By analysing the energy flow in a piezoelectric generator, it was revealed that the mechanical factor, electromechanical coupling coefficient and dielectric loss of the generator have significant influence on its energy conversion efficiency. Based on this analysis, aluminium nitrate (AlN) thin films deposited on stainless steel (SUS) were selected to substitute lead titanate zirconate thin films deposited on single-crystal Si for fabricating miniature devices. These thin films were prepared with an electron cyclotron resonance sputtering system. The influences of the surface modification (polishing or coating a Pt/Ti thin layer) of SUS substrates on c-axis orientation, piezoelectric coefficient and effective coupling coefficient of AlN thin films were investigated.

The Structure and Bonding State for Fullerene-Like Carbon Nitride Films with High Hardness Formed by Electron Cyclotron Resonance Plasma Sputtering

We studied pure carbon films and carbon nitride (CN) films by using electron cyclotron resonance (ECR) sputtering. The main feature of this method is high density ion irradiation during deposition, which enables the pure carbon films to have fullerene-like (FL) structures without nitrogen incorporation. Furthermore, without substrate heating, the ECR sputtered CN films exhibited an enhanced FL microstructure and hardness comparable to that of diamond at intermediate nitrogen concentration. This microstructure consisted of bent and cross-linked graphene sheets where layered areas remarkably decreased due to increased sp3 bonding. Under high nitrogen concentration conditions, the CN films demonstrated extremely low hardness because nitrile bonding not only decreased the covalent-bonded two-dimensional hexagonal network but also annihilated the bonding there. By evaluating lattice images obtained by transmission electron microscopy and the bonding state measured by X-ray photoelectron spectroscopy, we classified the ECR sputtered CN films and offered phase diagram and structure zone diagram.

An sp2 and sp3 Hybrid Nanocrystalline Carbon Film Electrode for Anodic Stripping Voltammetry and Its Application for Electrochemical Immunoassay

A hybridized nanocrystalline carbon film electrode consisting of sp(2) and sp(3) bonds was investigated to reveal the reduction properties of Cd(2+) and for application as a highly sensitive and reliable electrochemical immunoassay. Conductive nanocrystalline carbon film consisting of about 60% sp(2) and 40% sp(3) bonds was fabricated using electron cyclotron resonance (ECR) sputtering equipment, and then the Cd(2+) concentrations were measured with an ECR sputtered carbon (ECR nano-carbon) electrode by employing an anodic stripping voltammetry (ASV) technique. The preconcentrated Cd was analyzed with Kelvin probe force microscopy and energy dispersive X-ray spectroscopy while observing the morphology change with an atomic force microscope and a scanning electron microscope. The preconcentrated Cd on the ECR nano-carbon electrode was revealed to be a thin sheet structure, which was significantly different from the Cd on a conventional carbon material that grows with a coralloid structure. The background current during an ASV measurement maintains a low level equivalent to that found with boron-doped diamond because the surface of the ECR nano-carbon is robust and angstrom-level flat. The carbon-electrode performance for ASV was improved by controlling its structure at a nanometer scale without any metal doping or coating. Finally, the ECR nano-carbon was used for biomolecular determination by electrochemical immunoassay with a CdSe nanoparticle label. Electrochemical immunoassay results were successfully obtained with the ECR nano-carbon, and they correlated well with fluorescence results obtained for CdSe nanoparticles.

Electrochemical Determination of Oxidative Damaged DNA with High Sensitivity and Stability Using a Nanocarbon Film

We describe the electrochemical determination of oxidative damaged DNA by using a nanocarbon film electrode combined with a high performance liquid chromatography (HPLC) system. The nanocarbon film was formed by employing the electron cyclotron resonance sputtering method, and has a nano-crystalline sp(2) and sp(3) mixed bond structure with an atomically flat surface. This film electrode provided the high electrode activity and stability needed to quantitatively detect oxidative damaged DNA, 8-hydroxy-2'-deoxyguanosine (8-OHdG), by direct electrochemical oxidation. The coefficient of variation (C.V.) value of 1 µM 8-OHdG at our film electrode was 0.75% (n = 12), which constitutes superior reproducibility to that of a conventional glassy carbon (GC) electrode (9.28%, n = 12) in flow-injection analysis. This was because the nanocarbon film suppressed fouling for the oxidized product of 8-OHdG owing to its hydrophilically ultraflat and chemically stable surface. We also investigated the performance of HPLC with an electrochemical detection (HPLC-ECD) system using our nanocarbon film electrode. The detection limit for 8-OHdG at the nanocarbon film electrode was 3 nM, which was superior to the detection limit of the GC electrode (7.2 nM). Furthermore, this electrode was more suitable for use in a urinary 8-OHdG experiment than the GC electrode. The concentration of urinary 8-OHdG in the urinary sample was 8.30 nM. These results indicate that this HPLC-ECD system with our nanocarbon film electrode enables us to realize an accurate, sensitive, reproducible and easy to use analysis technique.

Defect Evaluation by Photoluminescence for Uniaxially Strained Si-On-Insulator

Uniaxial strain was introduced to Si-on-insulator (SOI) substrate by SiN deposition using electron cyclotron resonance sputtering followed by gate-opening using lift-off technique. Then thermal treatments were performed at different temperatures. Strain-relaxation was observed by Raman spectroscopy. Photolumine-scence (PL) was used to evaluate defects generated during strain-relaxation. Defect-related PL signal was observed for the thermally-treated strained channel. The intensity of defect-related PL signal increased with increasing annealing temperature. The energy position and profile of defect-related PL signal also varied with annealing temperature and SiN thickness.