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91.
BerndSchulz HarryJ.Levinson RolfSeltmann JoelSeligson PavelIzikson AnatRonen 《电子工业专用设备》2005,34(2):15-21,72
由于空间成像套刻(Overlay)技术的预算随集成电路(IC)设计规范的紧缩而吃紧,因此,Overlay测量技术准确度的重要意义也随之提高。通过对后开发(AfterDevelopDI)阶段和后蚀刻(AfterEtchFI)阶段的Overlay测量结果进行比较,研究了0.18μm设计规范下的铜金属双重镶嵌工艺过程中的Overlay准确度。在确保对同一个晶圆进行后开发(DI)阶段和后蚀刻(FI)阶段测试的条件下,我们对成品晶圆的5个工艺层进行了比较。此外,还利用CD-SEM(线宽-扫描电子显微镜)测量了某个工艺层(PolyGate)上的芯片内Overlay,并与采用分割线方法的光学Overlay测量结果进行了比较。发现对芯片内overlay的校准存在着严重的局限性,即在应用CD-SEM时缺乏合适的结构进行Overlay测量。我们还将继续为大家提供定量的比较结果,同时也会向大家推荐组合的CD-SEM测量结构,使其能够被应用到今后的光刻设计中。 相似文献
92.
Roger Chevrel Marcel Sergent Bernd Seeber Øystein Fischer Andreas Grüttner Klaus Yvon 《Materials Research Bulletin》1979,14(4):567-577
A new ternary molybdenum chalcogenide has been found with composition InxMo15Se19. This compound crystallizes in the hexagonal space group P63/m, and shows both types of blocks Mo6Se8 and Mo9Se11. To our knowledge, this is the first Me9X11 unit ever observed in a material. It presents a homogeneity domain: 2, 9 < x < 3, 4. Substitution of sulphur and tellurium for selenium in In3.3Mo15Se19-yXy (X = S, Te) is possible in the limits 0 < y < 12 and 0 < y < 2 respectively. The new compound becomes a high field superconductor at low temperature. 相似文献
93.
94.
Matthias C. Schulz Paula Korn Bernd Stadlinger Ursula Range Stephanie Möller Jana Becher Matthias Schnabelrauch Ronald Mai Dieter Scharnweber Uwe Eckelt Vera Hintze 《Journal of materials science. Materials in medicine》2014,25(1):247-258
Dental implants are an established therapy for oral rehabilitation. High success rates are achieved in healthy bone, however, these rates decrease in compromised host bone. Coating of dental implants with components of the extracellular matrix is a promising approach to enhance osseointegration in compromised peri-implant bone. Dental titanium implants were coated with an artificial extracellular matrix (aECM) consisting of collagen type I and either one of two regioselectively low sulfated hyaluronan (sHA) derivatives (coll/sHA1Δ6s and coll/sHA1) and compared to commercial pure titanium implants (control). After extraction of the premolar teeth, 36 implants were inserted into the maxilla of 6 miniature pigs (6 implants per maxilla). The healing periods were 4 and 8 weeks, respectively. After animal sacrifice, the samples were evaluated histomorphologically and histomorphometrically. All surface states led to a sufficient implant osseointegration after 4 and 8 weeks. Inflammatory or foreign body reactions could not be observed. After 4 weeks of healing, implants coated with coll/sHA1Δ6s showed the highest bone implant contact (BIC; coll/sHA1Δ6s: 45.4 %; coll/sHA1: 42.2 %; control: 42.3 %). After 8 weeks, a decrease of BIC could be observed for coll/sHA1Δ6s and controls (coll/sHA1Δ6s: 37.3 %; control: 31.7 %). For implants coated with coll/sHA1, the bone implant contact increased (coll/sHA1: 50.8 %). Statistically significant differences could not be observed. Within the limits of the current study, aECM coatings containing low sHA increase peri-implant bone formation around dental implants in maxillary bone compared to controls in the early healing period. 相似文献
95.
Andreas Heinrich Andreas L. Hrner Achim Wixforth Bernd Stritzker 《Thin solid films》2006,510(1-2):77-81
Surface Acoustic Waves on piezoelectric substrates can be used to investigate the dynamic conductivity of thin films in a non-contact and very sensitive way, especially at low conductivities. Here, we report on such surface acoustic wave studies to characterize thin manganite film like La0.67Ca0.33MnO3, exhibiting a Jan Teller effect with a strong electron phonon interaction and a metal insulator transition at high temperatures.
We report on the deposition of La0.67Ca0.33MnO3 on piezoelectric substrates (LiNbO3 in different crystal cuts, employing a pulsed laser deposition technique. The structural quality of the thin films are examined by X-Ray Diffraction, Scanning Electron Microscope and Energy Dispersive X-ray spectroscopy. For the electrical characterization, we employ the surface acoustic wave technique, accompanied by conventional direct current resistance measurements for comparison. 相似文献
96.
Brezesinski T Rohlfing DF Sallard S Antonietti M Smarsly BM 《Small (Weinheim an der Bergstrasse, Germany)》2006,2(10):1203-1211
WO3 thin layers with nanometer-scale periodicity were prepared by evaporation-induced self-assembly (EISA) using a novel amphiphilic block-copolymer template (poly(ethylene-co-butylene)-block-poly(ethylene oxide)). The evolution of the mesoporous ordered network and the crystallinity of the framework were monitored by 2D-SAXS, WAXS, SEM, XPS, and porosimetry. By annealing the films, the pore-wall crystallinity is adjusted between fully amorphous and highly crystalline without mesostructural degradation. Thus, the crystalline-film framework is composed of phase-pure monoclinic WO3 nanoparticles (12-14 nm in size). Furthermore, heat treatment transforms the originally spherical mesopores into ellipsoids, resulting in a unidirectionally shrunken, but still well-defined and fully accessible bcc mesopore architecture. The influence of mesoporosity and crystallinity on electrochemical/electrochromic characteristics was addressed by monitoring electrochemical features and the absorption changes during Li insertion/extraction (repetitive potentiostatic cycling). Both the amorphous and crystalline mesoporous films possess electrochromic response times on the order of only seconds, which are attributable to the facilitated insertion of guest ions due to shortening of the diffusion path lengths. Also, the insertion/extraction reversibility of crystalline WO3 layers with 3D mesoporosity is improved compared to amorphous ones and reaches values close to 100%. 相似文献
97.
Sandeep Gorantla Stanislav Avdoshenko Felix Börrnert Alicja Bachmatiuk Maria Dimitrakopoulou Franziska Schäffel Ronny Schönfelder Jürgen Thomas Thomas Gemming Jamie H. Warner Gianaurelio Cuniberti Jürgen Eckert Bernd Büchner Mark H. Rümmeli 《Nano Research》2010,3(2):92-97
In situ low-voltage aberration corrected transmission electron microscopy (TEM) observations of the dynamic entrapment of a C60 molecule in the saddle of a bent double-walled carbon nanotube is presented. The fullerene interaction is non-covalent, suggesting that enhanced π-π interactions (van der Waals forces) are responsible. Classical molecular dynamics calculations confirm that the increased interaction area associated with a buckle is sufficient to trap a fullerene. Moreover, they show hopping behavior in agreement with our experimental observations. Our findings further our understanding of carbon nanostructure interactions, which are important in the rapidly developing field of low-voltage aberration corrected TEM and nano-carbon device fabrication. 相似文献
98.
Microstructure strongly influences the mechanical properties of cast iron. By inoculating the melt with proper inoculants, foreign substrates are brought into the melt and eventually the graphite can crystallize on them. The elements and substrates that really play a role for nucleation are yet unknown. Until now there is very little knowledge about the fundamentals of nucleation, such as composition and morphology of nuclei. In this work we utilized EN-GJL-200 as a base material and examined several produced specimens. The specimens were cast with and without inoculants and quenched at different solidification states. Specimens were also examined with a high and low oxygen concentration, but the results showed that different oxygen contents have no influence on the nucleation in cast iron melts. Our research was focused on the microscopic examination and phase-field simulations. For studying the samples we applied different analytical methods, where SEM-EDS, -WDS were proved to be most effective. The simulations were conducted by using the software MICRESS, which is based on a multiphase-field model and has been coupled directly to the TCFE3 thermodynamic database from TCAB. On the basis of the experimental investigations a nucleation mechanism is proposed, which claims MnS precipitates as the preferred site for graphite nucleation. This theory is supported by the results of the phase-field simulations. 相似文献
99.
Nanomaterials for environmental studies: Classification, reference material issues, and strategies for physico-chemical characterisation 总被引:1,自引:0,他引:1
Vicki Stone Bernd Nowack Nico van den Brink Maria Dusinska Steven Hankin Erik Joner 《The Science of the total environment》2010,408(7):1745-1754
NanoImpactNet is a European Commission Framework Programme 7 (FP7) funded project that provides a forum for the discussion of current opinions on nanomaterials in relation to human and environmental issues. In September 2008, in Zurich, a NanoImpactNet environmental workshop focused on three key questions:
- 1.
- What properties should be characterised for nanomaterials used in environmental and ecotoxicology studies?
- 2.
- What reference materials should be developed for use in environmental and ecotoxicological studies?
- 3.
- Is it possible to group different nanomaterials into categories for consideration in environmental studies?
100.