超薄磁盘保护膜的制备技术

类金刚石薄膜和氮化硅薄膜都是性能很好的绝缘材料,可以用于对磁盘进行保护,在本文中主要讨论了它们各自的制备方法.随着巨磁阻读写磁头(giant magneto-resistive heads)技术的引入,磁盘的存储密度以每年100%的速度在增加,这就要求磁盘保护膜的厚度要尽量的小,所以对制备方法有一定的要求.对类金刚石磁盘保护膜,可以使用等离子体磁控溅射沉积、磁过滤阴极弧沉积、等离子体化学气相沉积来制备;对氮化硅磁盘保护膜,可以使用射频反应溅射沉积来制备.     

磁过滤真空弧等离子体钛沉积膜的XPS研究

通过磁过滤真空弧等离子体沉积技术,在单晶Si和H13钢衬底上生长一层Ti沉积膜。利用扫描电镜、X射线衍射仪和X射线光电子能谱仪对膜层进行了测量和分析。结果表明,加上磁过滤器的沉积膜表面平整光洁,无“液滴”出现。在靶室真空度不高的情况下,膜层中的Ti以TiO的形式存在,并且TiO晶粒沿<110>方向择优取向。膜层表面的TiO进一步与大气中氧发生反应形成TiO     

Hochstrom‐Filterbogen: eine neue Technik zur Abscheidung von Kohlenstoffschutzschichten in der Magnetspeichertechnologie. High Current Filtered Arc: a new Deposition Technique for Protecting Carbon Overcoats in Magnetic Storage Devices

Due to the lateral size reduction of stored bits on a hard disk, the head‐to‐media spacing has to be reduced as well as the thickness of the protecting carbon overcoats. In order to obtain a thickness in the 2 nm region a new process technology is needed. In the present paper, a high current pulsed arc (HCA) technique is presented as an innovative source for ultra thin carbon coating for future industrial disk production. The hardness and scratching resistance of these films are remarkable higher than conventional magnetron sputtered films. With the HCA‐Source we are able to produce pinhole‐free carbon films with thicknesses down to 2 nm. The deposition rate is 0.07 – 0.3 nm per pulse, therefore the coating time is below 2 sec per disk. The magnetic layer is left undamaged during the HCA deposition process. These aspects are very important for industrial disk production efficiency. Strong particle reduction due to a magnetic filter tube is confirmed by repeatable glide tests. Particles are confined in the magnetic filter tube and do not reach the substrate. In several important tests we showed that the HCA source is capable of producing carbon layers within a realistic disk production environment with a yield over 90 % which proved to be comparable to current magnetron sputtered overcoats.     

Three Filtered Vacuum Arc Plasma Sources Deposition & Implantation System

A deposition & implantation system, which includes three filtered vacuum arc plasma sources, has been built. Vacuum arc discharge is used to produce high-density metal plasma; Curved magnetic filtering technique is used to transfer the plasma into out-of-sight vacuum chamber and reduce macro-particles from the vacuum arc plasma in order to drastically reduce the macro-particles contamination of the films. The up to 30 kV negative bias applied to the target can be used for ion implantation in order to improve the film adhesion; or for ion sputtering to clear the substrate surface. The 0 to 300 V negative bias can be used to adjust the ion energy which forming films. The system is designed for various thin films synthesizing, such as single-layer, compound layer, multi-layer films. It's principle, components and applications are described in the literature.     

Abscheidung superharter Kohlenstoffschichten mittels Laser‐Arco® auf dem Weg vom Labor in die industrielle Serienfertigung

Superhard carbon film deposition by means of Laser‐Arco® on the way from the Laboratory into the industrial series coating Diamond‐like carbon films (DLC) are more and more applied as wear protection coatings for components and tools due to their unique combination of high hardness, low friction and sticking tendency to metallic counter bodies. Up to now applied DLC films are hydrogen containing (a‐C:H) or metal carbon films (Me‐C:H) deposited by a plasma assisted CVD process from carbon‐hydrogen gas mixtures. Their wide industrial effort results from that the can be deposited with slowly modified coating machines for classical hard coating (e.g. TiN or CrN). A new generation DLC films are the hydrogen‐free ta‐C films (ta‐C = tetrahedral bounded amorphous carbon) with a between two and three‐times higher hardness and with a resulting higher wear resistance under extreme condition than classical DLC films. They have excellent emergency running properties at lubrication break down. Their industrial application is more difficult due to that they cannot deposited with modified coating machines for classical hard and DLC coating and a new technology with corresponding equipment was not available up to now. The laser controlled, pulsed arc deposition technology (Laser‐Arco®) of the Fraunhofer IWS Dresden has this potential. In kind of a Laser‐Arc‐Module‐source the ta‐C film deposition can be integrated in every industrial used deposition machine.     

T-shape filtered arc deposition system with built-in electrostatic macro-particle trap for DLC film preparation

A T-shape filtered arc deposition system (T-FAD) is a powerful tool to prepare high-quality diamond-like carbon (DLC) films. Most macro-particles (droplets) emitted from the graphite cathode are caught at the extension duct of the droplet catcher or collector facing the cathode, and then the clean plasma bent 90° is transported toward the substrate. However, further droplet reduction is still required in order to realize a higher quality film without droplet incorporation. In the present study, T-FAD employed an electrostatic droplet trap (ES-trap). A cylindrical ES-trap was placed in the extension duct part of the T-shape duct of an electromagnetic plasma transportation and droplet filter. The ion current at the exit of the T-filter duct and the current flowing to the ES-trap were measured as a function of the ES-trap bias voltage for various ES-trap positions. The deposition rate and number of droplets were also measured. As a result, it was found that the optimum voltage of the ES-trap was + 35 V and that it was better to place the ES-trap closer to the plasma beam in order to obtain fewer droplets on the film without an excessive decrease in the deposition rate. In the optimum condition, the number of droplets on the DLC film prepared with ES-trap was reduced to 1/3 of that without the ES-trap.     

磁过滤阴极真空弧沉积装置研究中的等效电路方法

提出了模拟磁过滤阴极真空弧放电等离子体沉积装置阴极弧放电过程的等效电路 ,并用此电路定性研究了各参数对弧放电的影响 ,结果同实验符合的很好     

Transport of vacuum arc plasma through an off-plane double bend filtering duct

A new magnetic macroparticle filter design consisting of an off-plane double-bend (OPDB) filter is described. The transport of the vacuum arc plasma through this OPDB filter is investigated using Langmuir and deposition probes. Films of amorphous hard carbon have been deposited using a 90° single bend and the OPDB filter and the macroparticle contents of the films are compared. The experimental results were found to be in good agreement with the simulations results based on an improved drift approximation model. The results demonstrate that OPDB filter has a relatively better transmission efficiency than the 90° single bend filter, lower macroparticle counts and is suitable for preparation of diamond-like carbon coatings with high quality.     

Properties of SnO2 films fabricated using a rectangular filtered vacuum arc plasma source

Transparent and conducting SnO₂ films of 57–200nm thickness were deposited on microscope glass slide substrates, using a rectangular filtered vacuum arc deposition system. The 40 glass slides were equally distributed on a 400 × 420mm substrate carriage, and were exposed to a Sn plasma beam, produced by a rectangular vacuum arc plasma gun with a Sn cathode, and passed through a rectangular magnetic macroparticle filter towards the substrates. The carriage with the substrates was transported past the 94 × 494mm filter outlet. The SnO₂ films were fabricated on the glass substrates at room temperature by maintaining the chamber oxygen background pressure at 0.52Pa. The film composition, and electrical and optical properties were studied as a function of the film thickness. The films were stored under ambient air conditions, and their electrical resistance was measured as a function of storage time over a period of several months.

The average resistivity of films was 10–17mΩ cm for films with thickness (t) less than 100nm, but that of t > 100nm it was 5–9mΩ cm. The resistivity of the films with t > 100nm did not change significantly after 8months of storage in ambient air. The optical transmittance of the films in the visible spectrum was in the range of 75–90%. The optical constants, i.e., the refractive index and the extinction coefficient of the films at wavelength λ = 550nm were in the range of 2.02–2.09 and 0.013–0.023, respectively, and the optical band gap energy was 4.15–4.21eV. Unlike the electrical resistivity, the optical parameters weakly depended on t.     

Technisch‐wirtschaftlicher Review der Herstellung tetraedrisch‐amorpher Kohlenstoffschichten durch Lichtbogenverdampfen

Technical and economical review of the production of tetrahedral‐amorphous carbon films by vacuum arc evaporation Due to the high energy of the depositing species, vacuum arc evaporation is suited for the production of tetrahedral‐amorphous carbon coatings (ta‐C). As besides, the process allows for high deposition rates, it seems to be ideal for the deposition of ta‐C in industrial mass production. However, during the evaporation process inevitably macroparticles are formed, which also deposit on the parts to be coated, degrading the coating properties considerably. Therefore, measures are necessary in order to counter the formation and/or deposition of these particles. The following article intents to give an overview of possible measures and to subject them to a technical and economical evaluation in regard to their application in industrial mass production.     

Vakuummikro‐ und Vakuumnanoelektronik mit Feldemission

Vacuum microelectronics and nanoelectronics with field emission — features of breakdown voltage in vacuum gaps lower than 10 μm Further miniaturization in vacuum electronics will be possible only with field‐emitter cathodes. However in microscale vacuum gaps in the range 10 μm field emission is a dominant process in gas breakdown process, leading to signif icant deviations from the traditional Paschen's Law. At first a significant reduction of breakdown voltage is observed. The high surface‐to‐volume ratio in microscale dimensions 3 μm and in interactions with gas desorption, outgassing and gas ionization during electron field‐emission give a ignition and stabilization of micro plasmas (glow discharges) or/and micro arcs, which exist largely independent of surrounding vacuum, atmospheric or over pressure. In this range the Paschen's Law is invalid. This is an interesting approach which opens up new dimensions for basic research, field emission‐driven micro plasmas and for novel fieldemitter applications in vacuum electronics and plasma technology.     

Combined vacuum plasma surface treatment for increase of durability of face milling cutters from high‐speed steel

The article deals with the influence of the vacuum plasma surface treatment on the life of the face milling cutter of high‐speed steel R6M5 (analog M2 (USA, AISI/ASTM)). Such processing combines ion nitriding in gas plasma and the deposition of the wear‐resistant TiAlN layer in the metal gas plasma of the vacuum‐arc discharge. Research verifies that the use of vacuum plasma treatment combining the formation of the transition nitrided layer in the gas plasma and the subsequent deposition of TiAlN coating in metal gas plasma created by a vacuum‐arc discharge is an effective way to improve the tool life of high‐speed steel face milling cutters.     

Großflächenbeschichtung mit superhartem Kohlenstoff. Large area deposition of superhard carbon films

During the nineties the Laser‐Arc technology for the deposition of superhard amorphous carbon films (Diamor®) has been developed at the Fraunhofer Institute for Material and Beam Technology. This technology has now been scaled up by a factor of 4 compared to existing devices and integrated in an industrial large‐volume vacuum arc coater. First results demonstrate the possibility of depositing well adherent Diamor® films with a thickness of more than 2 microns and a hardness above 4000 HV on larger parts and tools. This opens a wide field of industrial applications.     

脉冲真空放电离子密度的测量

由于采用脉冲放电沉积技术能够克服连续电弧离子镀沉积时产生的液滴及负偏压放电的缺点，特别是它在镀制类金刚石薄膜中显示出来的独特性能：不含氢和硬度高，使其在薄膜沉积技术中越来越受到广大研究者的重视。为了更深入地研究薄膜的沉积工艺和薄膜性能之间的关系，迫切需要对脉冲真空放电等离子体的微观参数进行深入透彻的研究，如离子密度及其空间分布等。本文介绍了测量脉冲真空电弧离子源离子密度的方法，并采用该方法测量了脉冲真空电弧离子源离子密度及其空间分布，分析和研究了影响离子空间分布的各种参数。     

Vakuumbeschichtung – Heutiger Stand und zukünftige Trends

Thin films have changed the world. Many products of our modern life, like powerful PC's, the Compact Disc, or energy-saving architectural glazings would not exist without vacuum coating technology. During the past 20 years PVD and PECVD processes for deposition of thin films have spread into a huge variety of different applications. Besides microelectronics, the major fields for the near future are flat panel displays, data storage, optics/glass and surface protection. The article outlines today's market situation and tries to characterize present status and future trends in vacuum coating technology on the basis of some selected examples.     

非晶金刚石薄膜的制备及其性能研究

本文利用一种新的等离子体沉积技术－真空磁过滤弧沉积制备得到一种无氢的非晶碳膜。ＥＥＬＳ分析表明，这种非晶碳膜几乎不含有ｓ０＾２和ｓｐ杂化键，呈现出高度的金刚石特征，以致可以被称为非晶金刚石膜。     

Hemocompatibility of ZnO thin films prepared by filtered cathodic vacuum arc deposition

Zinc Oxide (ZnO) thin films were prepared by cathodic vacuum arc deposition (CVAD) and filtered cathodic vacuum arc deposition (FCVAD) technology with a mixture of O₂, Ar and N₂. XRD patterns indicated that ZnO thin films prepared by CVAD had a combined orientation of ZnO (002) and ZnO (101). The preferential orientation ZnO (002) could be obtained at an optimum deposition pressure. On the other hand, a perfectly oriented ZnO (002) thin film prepared by FCVAD was obtained in lower pressure, which was beneficial to enhance the crystallization. The wetting behavior showed that all the ZnO thin films prepared by FCVAD were hydrophobic with low surface energy, but the reference samples of the polyurethane (PU) and glass are hydrophilic. Platelet adhesion test indicated that fewer platelets adhered and aggregated on the ZnO thin films prepared by FCVAD. The mechanism of hemocompatibility of ZnO thin films has also been investigated. It is suggested that hydrophobic surface with lower polar component and adhesive work are the two factors responsible for the excellent hemocompatibility.     

Superharte amorphe Kohlenstoffschichten

Carbon films are distinguished by their special properties and the broad structural spectrum. Amorphous carbon films with dominating tetragonal bonds (ta‐C films) represent a high potential for tribological applications by their combination of superhardness and low adhesion. With the pulsed vacuum arc methods there are now industrial technologies available for the deposition of these promising protective coatings.     

超高分子量聚乙烯表面金属化及类金刚石薄膜沉积复合处理研究

采用超高分子量聚乙烯(UHMWPE)表面金属化及类金刚石薄膜沉积复合处理工艺,提高超高分子量聚乙烯的耐磨性.首先采用磁过滤阴极真空弧源沉积技术(FCVA)在UHMWPE表面制备约30nm钛金属层,使UHMWPE表面金属化,然后再沉积DLC薄膜,研究结果表明,UHMWPE表面金属化后,DLC薄膜沉积过程中,电荷累积效应消...     

Diamantartige Kohlenstoffschichten steigern die Effizienz

Diamond‐like carbon thin films enhance efficiency — laser arc deposition of ta‐C Rising prices for fossil fuels as well as the increasing effects of the climate change due to the emission of greenhouse gases reveal the necessity of saving energy. Low friction coatings have an enormous potential in saving energy. Carbon based coatings — named as DLC coatings — are especially well suited for low friction coatings. In particular hydrogen‐free tetrahedral amorphous carbon (ta‐C) coatings are of great interest due to their extraordinary low wear properties. In addition they show excellent low friction properties and especially in combination with specific lubricants the so‐called super low friction effect. For the deposition of ta‐C coatings PVD methods have to be applied instead of CVD methods as it is the case for conventional DLC coatings. We have developed a deposition method which is based on a pulsed arc steered by a laser (Laser‐Arc). This allows us to use large cathodes resulting in a high long‐term stability. Furthermore, the carbon plasma source can be combined with a filtering unit removing almost all droplets and particles, which usually are characteristic for an arc process. The resulting Laser‐Arc source allows for the deposition of smooth and virtually defect‐free ta‐C coatings with a competitive deposition rate.