共查询到20条相似文献,搜索用时 31 毫秒
1.
The combination of in situ spectrophotometry during film deposition and ex situ spectrophotometry allows insight into the depth distribution of optical losses in plasma ion assisted deposition coatings. An adapted optical characterization strategy for absorbing coatings using only in situ transmittance data has been developed and is exemplified in application to magnesium fluoride coatings. Measurements and simulation results strongly indicate an increased absorption caused by local understoichiometry of the fluoride material close to the fused silica substrate. 相似文献
2.
Michael Scherer Dr. 《真空研究与实践》2009,21(4):24-30
For many applications there is an increasing request to control the deposition process on an atom layer scale. This offers a lot of advantages like in accuracy, layer homogeneity and tailoring of layer properties. On the other hand the speed and throughput of the process should not suffer from the control on an atom layer scale as it is the case for classical atom layer deposition (ALD). For optical applications especially high‐end interference filter coatings we developed a plasma assisted reactive magnetron sputtering process in combination with a high speed drive for the substrates. This combination allows controlling the layer thicknesses and layer properties on an atom layer scale while maintaining a high deposition rate. The advantages of this process are demonstrated on single layer results of SiO2, HfO2, ZrO2, Ta2O5 and mixed oxides of SiO2‐Nb2O5. Morphology, surface roughness, film stress, refractive index and losses are controlled by the oxygen partial pressure, the substrate temperature, the energy input by the sputtering ‐and assist process and by cosputtering. The outstanding performance of high‐end interference filter coatings like a multi notch filter for fluorescence microscopy is achieved by the very stable and reproducible deposition process in combination with an advanced thickness control strategy based on in‐situ optical thickness control and time control. 相似文献
3.
Michael Vergöhl 《真空研究与实践》2000,12(6):364-366
For the deposition of modern coatings on architectural glass (energy‐saving, solar control, anti‐reflective), reactive magnetron sputtering plays an outstanding role. The production of these coatings by reactive sputtering requires a manufactoring equipment, that ensures high quality as well as efficient deposition of the coatings. Thin film measurement by in‐situ ellipsometry can very impressively used for monitoring and controlling the film properties, in particular in the case of more complex coatings. With regard to long‐term stability the in‐situ film measurement is of special importance with respect to the use of the novel mid‐frequency magnetron sputter technique. This technique allows the deposition rate to be increased up to 500 %, however, a dynamical plasma stabilization in the so called »transition mode« is necessary. Within the framework of a project supported by the BMBF, the spectroscopic ellipsometry was implemented on a large scale glass deposition plant (Semco Glasbeschichtung, Neubrandenburg) and was tested during the production. The investigations show that ellipsometry is outstandingly suitable for an accurate determination of the optical layer properties of coatings on architecture glass, even for complex layer systems. Therefore, the basis for an improvement of the efficiency of the plant is given. 相似文献
4.
The paper discusses approaches to the insitu analysis of optical multi‐layer coating stacks such as mirror coatings, AR coatings or lowE layer stacks on large‐area substrates in production environments. The stable production of complex layer systems requires in‐situ analysis systems that are able to provide spectral information and optical performance data, but also yield thickness information for individual layers and thus aide the operating staff in detailed analyzing deviations from the production target stack. Solutions incorporating in‐situ optical reflectance, transmittance and ellipsometry measurements with optical data being collected not only for the completed layer stack, but also at intermediate coating stages, are discussed and the accuracy, robustness and stability of different measurement systems and computation strategies are compared. 相似文献
5.
A new optical monitoring system has been developed that allows recording of transmission spectra in the wavelength range between 400 and 920 nm of a growing optical coating during deposition. Several kinds of thin film sample have been prepared by use of a hybrid monitoring strategy that is essentially based on a combination of quartz monitoring and in situ transmission spectra measurements. We demonstrate and discuss the applicability of our system for reengineering procedures of high-low stacks and measurements of small vacuum or thermal shifts of optical coatings. 相似文献
6.
Modelling the NIR/VIS/UV optical constants of thin solid films: An oscillator model approach Based on a multioscillator approach, we demonstrate the determination of optical constants of different optical coating materials. The advanced LCalc‐software allows calculating the dielectric function as well as refractive index and extinction coefficient through a fit of transmittance and reflectance spectra measured at one or several angles of incidence. Sufficiently accurate spectrophotometric measurements are carried out by means of self‐developed VN‐ The thus obtained optical constants are automatically Kramers‐Kronig‐consistent and in reasonable correspondence to various kind of side information available about the coatings. This is demonstrated for dielectric oxide coatings as well as for one transparent conductive oxide (ITO) and a metal layer (aluminium). In application to reproducibility experiments, the method allows estimating process‐inherent stochastic variations in optical constants, which represent themselves an essential input for advanced computational manufacturing runs for design optimization prior to deposition. 相似文献
7.
The combination of atomic force microscopy (AFM) with infrared attenuated total reflection (IR-ATR) spectroscopy for simultaneous spectroscopic evanescent field absorption and scanning probe measurements is presented. The capabilities of the combined setup are demonstrated by in situ AFM imaging of the dissolution process of urea in a cyclohexane/butanol solution with nanometer topographical resolution, while simultaneously recording the correlated bulk spectral changes by mid-infrared evanescent field absorption spectroscopy. Hence, surface modification processes such as dissolution or deposition can be simultaneously monitored by AFM imaging and IR spectroscopy in liquid environments, which has not been demonstrated to date. This combined technique will in the future enable kinetic studies on physical, chemical, and biological processes at a wide variety of surfaces providing chemical specificity via IR spectroscopy in addition to high-resolution imaging via AFM. 相似文献
8.
O'Mongain E Buckton D Green S Bree M Moore K Doerffer R Danaher S Hakvoort H Kennedy J Fischer J Fell F Papantoniou D McGarrigle M 《Applied optics》1997,36(21):5162-5167
A submersible marine radiometric spectrometer system, capable of simultaneous measurements of the in situ spectral and angular properties of the underwater oceanic light field, is used to determine spectral inherent optical properties of marine waters. The inversion methods used to convert the sampled light field measurements into estimates of spectral absorption are presented and sample results for three water types obtained during a cruise in the North Sea are given. 相似文献
9.
Open multipass absorption cell for in situ monitoring of stratospheric trace gas with telecommunication laser diodes 总被引:1,自引:0,他引:1
A two-mirror multipass absorption cell that is operated open to the atmosphere from a stratospheric balloon to monitor in situ methane (in the 1.65-microm region) and water vapor (in the 1.39-microm region) with telecommunication laser diodes is described. A small Cassegrain-type telescope is used to couple the cell simultaneously with two near-infrared InGaAsP laser diodes by means of optical fibers. The 1-m cell provides an absorption path length of 56 m. The optical cell was carefully designed to be free of incidental fringing in the 10(-5) absorption range. It is used in combination with a dual-beam detector to obtain a detection limit of 10(-5) absorption units, a large dynamic range of the measurements of many orders of magnitude, and a precision error in the concentration determination of a few percents. The optical arrangement of the cell and its ability to be used to detect in situ trace gas in the stratosphere, in severe environmental conditions, are exposed. 相似文献
10.
John Fahlteich Dr. Matthias Fahland Dr. Steffen Straach Steffen Günther Dr. Nicolas Schiller Dr. 《真空研究与实践》2011,23(4):29-37
Transparent permeation barrier layers on flexible polymer substrates This paper reviews different vacuum based technologies for manufacturing transparent permeation barrier layers and layer stacks on flexible polymer substrates. With plasma assisted reactive evaporation, a cost‐efficient, highly productive process for food packaging applications is presented. Reactive dual magnetron sputtering is a technology for the deposition of oxide layers with a very low water vapor and oxygen transmission rate at a reasonable deposition rate. Many groups suggest multilayer stacks for the encapsulation of flexible electronic devices. In this paper, an all‐in‐vacuum inline concept for manufacturing such multilayers is presented. It is based on the combination of reactively sputtered barrier layers with interlayers grown by using a magnetron based PECVD process (Magnetron‐PECVD). Both, process parameters, such as deposition rate and process pressure, and important layer properties, such as morphology and the water vapor and oxygen transmission rate are compared for the different single and multi layer technologies. 相似文献
11.
Spectroscopy measurements made through a continuum having suspended particulate matter are addressed. The applications presented permit correction of spectral transmissions as effected by particulate-producing fossil-fuel combustion. The research is especially applicable to large effluent flows from coal-fired power plants, whose effluents are studied with in situ (smokestack) radiometers. Methods involving fast calculation procedures based on measured irradiances in unabsorbed regions of the IR spectrum are presented. The methodology is based on wavelength-dependent extinction of radiation by small particles, considering both elastic scattering and absorbing effects. This extinction leads to an observed skeweness (or shift) of the blackbody spectral shape. Based on such skeweness, the particulate number distribution is determined with Mie theory. In order to simplify, and to speed up the routine for real-time application, a two-step procedure is presented. During preinstallation calibration with Mie theory, sets of integral tables are computed for all possible solution values and stored in computer memory. Based on instantaneous spectral measurements, the appropriate integral tables are retrieved, then used as inputs in a process leading to particulate number distribution. Because all time-consuming calculations associated with Mie theory are performed during preinstallation calibration, the technique is capable of monitoring particulate emission in real time. Furthermore, given resolution of the number distribution in combination with thermodynamic analysis of the system, determination of particulate apparent density and particulate mass flow rate is made. These values have importance for environmental reporting. Comparisons of calculated particulate distributions with in situ measurements are also presented. Confirmatory testing programs conducted at several power plants are discussed. 相似文献
12.
In situ optical monitoring and process control: Measuring transmittance and reflectance of optical coatings during deposition Optical monitoring techniques havebecome indispensable parts of deterministic preparation strategies for sophisticated optical coatings. Traditional versions of optical broadband monitoring are based on measurements of the transmission spectrum or alternatively the reflection spectrum of the growing film. In the case of practically loss‐free samples, both approaches principally deliver equivalent information. In the case of absorbing coatings, the information gained from the different spectra may be no more equivalent. Instead, it may be reasonable to record both spectra simultaneously, in order to get a more complete picture of the status of the growing film. We present a corresponding measurement setup designed for use in typical coating evaporation processes and demonstrate its application to the deposition of alumina coatings as well as aluminum mirrors. 相似文献
13.
Optical interference filter on polymer films - Spectral channel separation in 3-D projections by wavelength division multiplexing In this work the preparation of optical interference filters on polymer foils for spectral channel separation for 3D projections is presented. The suitability of various polymer substrates for this purpose was investigated by measurements of the layer adhesion and the optical haze. Optimization of the energy input during the coating process and of the optical layer design offered a possibility to coat optical interference layer systems for spectral channel separation on PET polymer foil. It was possible to build working 3D glasses. Furthermore the application of gradient filters for the compensation of the spectral shift due to different incident angles and the processing of the coated filter foils were discussed. 相似文献
14.
The absorption spectrum of the NO A2Σ+ ← X2Πγ-system can be used for in situ evaluation of gas temperature. Experiments were performed with a newly developed atmospheric-pressure
high-temperature flow gas cell at highly uniform and stable gas temperatures over a 0.533 m path in the range from 23 °C to
1,500 °C. The gas temperature was evaluated (1) from the analysis of the structure of selected NO high-resolution γ-absorption
bands and (2) from the analysis of vibrational distribution in the NO γ-absorption system in the (211–238) nm spectral range.
The accuracy of both methods is discussed. Validation of the classical Lambert–Beer law has been demonstrated at NO concentrations
up to 500 ppm and gas temperatures up to 1,500 °C over an optical absorption path length of 0.533 m. 相似文献
15.
The diffusion and coalescence of Au–Cu alloy nanoparticles was studied at high magnification using in situ transmission electron
microscopy. The particles prepared by physical vapor deposition onto amorphous-C support films had an average composition
of Cu–43 at% Au and diameters of 15–50 nm. In the case analyzed, the larger of two nanoparticles remained stationary throughout
the coalescence process while a smaller nanoparticle moved toward the larger particle at a temperature of ~573 K. The surface
of the small nanoparticle was observed to fluctuate while approaching the larger particle, demonstrating that collective atom
process occurs along the particle periphery. The particle also decreased in size during the process, indicating that it was
losing mass as well as migrating. Direct evidence of a diffusional flux between particles was observed before the coalescence
process. The small nanoparticle coalesced into the large one at a highly accelerated rate compared to its prior migration. 相似文献
16.
High‐temperature testing in a Charpy impact pendulum using in‐situ Joule heating of the specimen
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P.A. Ferreirós P.R. Alonso P.H. Gargano G.H. Rubiolo 《Fatigue & Fracture of Engineering Materials & Structures》2018,41(5):1171-1182
In this paper, an innovative approach to high‐temperature testing of subsize Charpy V notched specimens is introduced. The design concept is to heat the specimen on the specimen piece supports up to the moment of impact by flowing AC electric current through it. This approach allows a very accurate centring of the specimen with respect to the anvils and the control of their temperature up to the moment of impact. The temperature profile measured by using the in‐situ heating device on ferritic steel specimen over the notch temperature range of 400°C < T < 750°C is presented. The impact energy was measured at different temperatures going through the eutectoid phase transformation of the ferritic steel specimens, with different carbon composition, to investigate the validity of the instrumented in‐situ heating method. The method is particularly appropriate to estimate the ductile brittle transition that occurs at high temperature in some metallic alloy systems. Also, its wide range of specimen heating rate provides new research tools for studying, for example, the intermediate temperature embrittlement of metals and alloys. 相似文献
17.
High-accuracy spectral-slit-function calibration measurements, in situ ambient absorption gas cell measurements for ozone and nitrogen dioxide, and ground-based zenith sky measurements with the Earth Observing System Aura Ozone Monitoring Instrument (OMI) flight instrument are reported and the results discussed. For use of high-spectral-resolution gas absorption cross sections from the literature in trace gas retrieval algorithms, accurate determination of the instrument's spectral slit function is essential. Ground-based measurements of the zenith sky provide a geophysical determination of atmospheric trace gas abundances. When compared with other measurements, they can be used to verify the performance of the OMI flight instrument. We show that the approach of using published high-resolution absolute absorption cross sections convolved with accurately calibrated spectral slit functions for OMI compares well with in situ gas absorption cell measurements made with the flight instrument and that use of these convolved cross sections works well for reduction of zenith sky data taken with the OMI flight instrument for ozone and nitrogen dioxide that are retrieved from measured spectra of the zenith sky with the differential optical absorption spectroscopy technique, the same method to be used for the generation of in-flight data products. Finally, it is demonstrated that the spectral stability and signal-to-noise ratio performance of the OMI flight instrument, as determined from preflight component and full instrument tests, are sufficient to meet OMI mission objectives. 相似文献
18.
O. R. Ghita M. A. Beard J. McCabe R. Bottom J. Richmond K. E. Evans 《Journal of Materials Science》2008,43(14):4988-4995
Thermal and spectral analysis is conducted routinely to characterise a large range of materials and compounds. However, tests
are often conducted independently on separate samples where comparison between essentially the same material can provide conflicting
results. Simultaneous thermal and spectral measurements have the advantage of being able to directly compare results using
the same sample. A novel design of a simultaneous thermal and spectral technique is described along with application examples
that highlight the benefits of this technique. The thermal analysis was conducted using Differential Scanning Calorimetry
(DSC) and the in situ spectral analysis was conducted using a Fourier Transform Near Infrared (FT-NIR) spectrometer. Two examples
are used to illustrate the versatility and potential advantages of the combined thermal and spectral method. Analysis of the
first and second order transitions of polyethylene terephthalate (PET) is presented along with the pharmaceutical polymorphic
conversion of carbamazepine from Form III to Form I through an isothermal hold at 160 °C. 相似文献
19.
20.
An in situ monitoring setup and process control loop were developed and integrated into a magnetron sputtering coater equipped with a Sentech SE 401 single wavelength ellipsometer, including the engineering of software for in situ process control to enhance production accuracy. By using that software, the system allows direct monitoring of the layer thickness on a moving substrate. It is shown that it is possible to determine the complex index of refraction from the distribution of measurements depending on the layer thickness. A strategy has been developed for in situ reverse thickness engineering of the top layers to compensate measurement errors. 相似文献