Film Heads Research Articles

Research on Design Expression and Design Method of Film Head Production Based on Computer Software

The beginning of the film and television film has a very unique style and has very special personalized characteristics. The film and television film head is designed by perfectly combining the visual art and expression content of the image, which not only includes the deep artistic cultivation, but also includes the comprehensive knowledge of the designer based on multi-angle of view, so that the field of visual communication can be broadened. In order to have a more powerful technology to support film and television title creation and design, to provide it with a broader artistic expression possible. At the same time, there are updates and higher standards for film and television title creation, but the development of advanced technology provides more choices for creators, but also gives designers more challenges, and urges creators to design more expressive film titles. In addition, the aesthetic needs of the audience have been significantly improved, promoting creators to carry out continuous innovation. This paper analyzes the design expression form of film and television title production, and then discusses the design method in film and television title design based on computer software.

An improved patent similarity measurement based on entities and semantic relations

Abstract Patent similarity measurement, as one of the fundamental building blocks for patent analysis, is able to derive technical intelligence efficiently, but also can detect the risk of infringement and evaluate whether the invention meets the criteria of novelty and innovation. However, traditional approaches make implicitly several assumptions, such as bag of words in each component, semantic direction irrelevance and so on. In order to relax these assumptions, this study proposes an improved methodology on the basis of entities and semantic relations (functional and non-functional relations), which takes semantic direction of each sequence structure and the word order information of each component into consideration. Meanwhile, an algorithm for calculating the global importance of each sequence structure is put forward. Finally, to verify the effectiveness and performance of the improved semantic analysis, a case study is conducted on the thin film head subfield in the field of hard disk drive. Extensive experimental results show that our approach is significantly more accurate.

From the Hood to the White House: The Cultural Imaginary of Presidential Blackness in Head of State

This article analyzes the film Head of State’s cultural imaginary of presidential blackness that signifies national progress while sublimating social conflict. The plot imagines a black man from the hood successfully running for presidency, living the American dream, and becoming an unconventional national icon. His symbolic blackness comprises two markers of difference: his identification with the disenfranchised hood and the black diaspora. As he challenges racial inequality in the U.S. as well as moral corruption among the élite, he unifies one historical fiction of America. I focus on how the film attributes an anti-establishment legacy to a minority president based on his countercultural identity performances although he remains complicit with foundational institutions of government. While the film projects hopes for future racial and economic equality upon a fictional black president and strategically redefines the American dream, I argue that it appropriates and revives American exceptionalist myths.

Entrevista com Céline Ruivo

Céline Ruivo é diretora de coleções de filmes da Cinémathèque française (2011) e coordenadora da Comissão Técnica da FIAF (2016). Formada em Cinema pela Université Paris 1 - Panthéon-Sorbonne e doutora pela pela Université Paris 3 – Sorbonne Nouvelle, passou ainda pela Université Paris 8 (Master Válorisation du Patrimoine cinématographique et audiovisuels) e pela Selznick School da George Eastman House. Seu percurso de formação e profissional é exemplar de uma nova geração de preservacionistas audiovisuais que vêm aos poucos ocupando postos-chave nas principais instituições de guarda e conservação do patrimônio audiovisual. A entrevista foi realizada em setembro de 2018 na Cinemateca do MAM do Rio de Janeiro.

From the Lab to Scaling-up: Case Studies of Electrodeposition Processes in the Photovoltaic Industry

Photovoltaic (PV), with more than 300 GW of cumulative capacity installed by the end of 2016, represents about 1.5% of the world electricity production. It is now obvious that the growth of PV will not only continue but even accelerate, as a key player for the energy transition, reaching up about 5 TW by 2050, as projected by the International Energy Association. The main reason for this development is due to a reduction by 10 of PV electricity cost in ten years. This trend makes PV electricity competitive with classical fossil or nuclear electricity in many regions of the world. The decrease in cost has resulted from improvement in materials and methods, an increase in solar energy conversion efficiency and in volume production. Research and Development plays a major role in this process proposing innovation and scientific breakthroughs in existing PV technologies and introduction of new technologies. Scaling effects have played a key role in decreasing the production costs but further progress along with innovative technologies will be needed to lower costs. The comparison between thin film technologies and wafer based technologies is typical of this paradigm. Thin film technologies are basically coating technologies which are inherently better adapted for large area processing (thousands of km2) compared to slicing individual crystalline wafers and assembling them as a mosaic. However, any defect on a part of a large area process induces a huge impact on the whole panel where the slices of Silicon are sorted to produce module. Moreover, the cost reduction of the wafer technology with scaling and the industrial maturity of silicon technology is so rapid that this technology is cost leading. As a consequence, the PV industrial sector is dominated at more than 90% by Silicon solar cells. The remaining 10% is composed of vacuum based thin films. Electrodeposition, despite intrinsic advantages, with real success in industry with, among numerous other examples, damascene copper in semiconductor or permalloys in thin film head, is almost absent of this PV industrial landscape. However, introduction of plating will be easier and more probable for new cell technologies, where new investment has to be done and for which stringer requirements emerge. In this context, we will discuss and make some prospective about two case studies involving electrodeposition in PV: plating contacts on Silicon and Cu-In-Ga based plating for thin films solar cells. On Silicon PV market, Copper represents an alternative to Silver screen printing. Copper has a much lower price than Silver with an equivalent bulk resistivity. Interdigited Back Contact (IBC) and Heterojonction (HJT) solar cells with Cu plating already exists for years. Nonetheless, Cu being a lifetime killer in c-Si, a Ni diffusion barrier is usually used. This approach has been demonstrated for front side metallization, based on Light Induced Plating. The case of emerging bifacial solar cells will be specifically discussed with the use of Ni/Cu or Ni/Ag plating. The remaining challenges will be discussed, including specificity of plating on both sides simultaneously, surface roughness issue and his impact on adhesion, ghost plating linked to surface passivation defects. For producing thin film solar cells, an alternative to vacuum based deposition methods (co evaporation, sputtering), which are presently used, is to use electrodeposition or printing. We will make a comprehensive description of the scale-up of the electrodeposited CIGS precursor layers from the laboratory scale of a rotating disk electrode to a full-size 60 cm x 120 cm compatible with 1 m2/min production of solar panels. More specifically, we will discuss the different fabrication approaches for electrodeposited precursor CIGS materials, development and recycling of solution chemistries for Copper, Indium and Gallium. Resulting fabrication of solar cells will be described. We will also present applications and devices which specifically take advantage from electrodeposition approach that is localized deposition on patterned substrate. The specific mechanism of electrodeposition in microelectrode array configuration and the challenge of upscaling will be discussed. References L. Tous et al, Energy Procedia 124, 922–929 (2017). Q. Huang, et al, Journal of The Electrochemical Society, vol. 158, issue 2, 2011, D57-D61 P.-P. Grand et al, WO 2012/052657 C. Broussillou et al, IEEE, New Orleans (2015) A. Duchatelet et al, Applied Physics Letters, 109 (2016), 253901

Cinephiles, Criminals, and Children: Discourses and Practices of Cinema Education in 1920s Paris

Cinephiles, Criminals, and Children: Discourses and Practices of Cinema Education in 1920s Paris Annie Fee (bio) In the June 2014 report “For a European Film Education Policy,” commissioned by head of the Centre National du Cinéma (CNC), Frédérique Bredin, Xavier Lardoux stressed the need to bring schoolchildren into cinemas, “a sacred space where others have gone before us, and have experienced moments of intense feeling, drama or joy,” so that they might “discover works of cinematic art” and thus create “Europe’s film-loving cinema-goer of the future.”1 The following year Lardoux, by then head of film at the CNC, shared the results of his report at the Cinémathèque Française for the launch of the MEDIA funded program “A Framework for Film Education in Europe,” headed by the British Film Institute (BFI). The program, though Europe-wide in scope, was launched at the symbolic seat of French cinephile culture, and Lardoux’s report had its origins in the former French Minister of Culture Aurélie Filippetti’s speech at the 2013 Cannes Film Festival. From the perspective of French cultural institutions, then, efforts to implement film education in twenty-first century European schools take place through a framework of classical cinephilia and should, in Frédérique Bredin’s words, pay particular attention to “the artistic dimension of film” and “its very particular relationship with the movie-theatre.”2 This close connection between cinephilia as an intellectual culture of film appreciation and contemporary notions of film education has origins so deeply rooted in the early history of cinephilia that the two are difficult to distinguish. Cinephilia has from the beginning defined itself as an antidote to mere commercial film production, the bulk of which comes from Hollywood studios, giving cinephilia an identity both European and highbrow but also forcing it to [End Page 38] continuously work to ensure financial support and cultural recognition from official circles. The task of initiating new generations of cinemagoers to cinephilia has therefore always been a matter of life and death. As Pascal Laborderie reminds us, “cinephilia was founded” on “educational terrain” during the interwar period, when “the combined actions of the Offices du cinéma éducateur and of the secular teaching leagueLigue de l’enseignement prepared the ground for a popular secular educational cinema which would foreshadow non-commercial cinema legislation and prepare the explosion of the ciné-club movement.”3 The non-commercial cinema legislation to which he refers is the 21 September 1949 decree granting tax exoneration for non-commercial film, followed in 1959 by the avance sur recettes policy, a hard-won set of decrees that recognized artistic film as an alternative to what had since the interwar years been widely seen as the “immoral” entertainment of commercial cinema by relieving them of punitive taxes. To the issue of morality one might add the perception, common in the interwar French film industry, that French audiences were being inundated with American productions, a cultural invasion that threatened interwar French cinema with irrelevance but also furnished the struggling industry with an effective argument with which to convince statesmen of the importance of supporting filmmakers who sought to elevate French film to the level of high art.4 The eventual success of classical cinephilia in achieving official recognition as a practice of critical spectatorship and creation worthy of state support, thanks to the efforts of Louis Delluc and the French First Wave critics, has overshadowed the myriad ways in which various other communities, from state elites to working-class social activists, envisioned cinema as a pedagogical and political medium amenable to objectives that were not necessarily in agreement with those of the cinephiles. Louis Delluc, Ricciotto Canudo, and Émile Vuillermoz used ciné-club lectures and film journals as sites of cinephile training for their target audience, an audience that was largely limited to the small number of upper-middle-class Parisians who could further their agenda. Because the existing historiography of the ciné-club movement focuses on this elite community of intellectual film-makers, we are left to wonder how communities outside of their rarified circles saw cinema as an educational tool in 1920s Paris...

The First Thin Film Electronic Package

The magnetic thin-film head, announced by IBM in 1979, marked the transformation of electrochemical technology from a shop art to a precision manufacturing process with far wider applications than the thin film head. An important application of electroplating was in the fabrication of the multichip module that provided the packaging for chips in advanced computers. These modules included copper strip lines for data transmission between chips. To minimize pulse distortion, these lines had to have precisely controlled propagation characteristics, and plating through a lithographic mask was the most effective way to insure the tight control on the geometry of the lines necessary to meet this requirement. This paper highlights the evolution of packaging for computers and tells how the scientists and engineers from the IBM T.J. Watson Research Center who had created the thin film head, worked with the development and manufacturing groups at IBM’s East Fishkill plant to bring electrochemistry into the manufacture of advanced packaging modules.

The First Thin Film Electronic Package: From Invention to Manufacturing

As late as the end of the 1970’s, electroplating was regarded as a mystical shop art that had no place in microelectronic fabrication. In 1979 IBM introduced a magnetic thin film head made possible by a newly invented process that was based on electroplating – an achievement that cast electroplating in a new light. Today, electroplating has spread into applications ranging from nanoscale patterning of copper BEOL wiring below 10 nanometers on silicon chips to the deposition of materials for synthesis into photovoltaic layers on 60 cm by 120 cm solar panels, and has also made possible the use of metal structures in MEMS devices. The successful production of the thin film head with its precisely patterned high aspect ratio copper coils and its permalloy elements with tightly controlled magnetic properties, which plating experts of the 1970’s deemed impossible to do by plating, made device fabricators receptive to the electrochemical technology they once shunned.An important new application of electroplating technology was in the fabrication of the multichip module. In advanced computers, these modules were multilayer ceramic structures that provided the power connections to the circuit chips and had a top layer of copper strip lines for data transmission between chips. The strip lines consisted of copper conductors with a rectangular cross-section that might be 6 µm high and 10 to 20 µm wide embedded in polyimide between two ground planes. These structures, which were essentially low-loss transmission lines, had to have precisely controlled propagation characteristics to minimize pulse distortion. Plating through a lithographic mask was an effective way of insuring the tight control on the geometry of the lines necessary to meet this requirement. One aspect of this talk will be to highlight the technical aspects of integrating electrochemical technology into the fabrication process for the transmission lines. The other will address how the scientists and engineers from the IBM T.J. Watson Research Center who had created the thin film head, worked with the development and manufacturing engineers at IBM’s East Fishkill plant to bring electrochemistry into their production line.

Keynote: Thin Film Magnetic Heads: Break-through of Electroplating into Electronics, Quantum Jump in Magnetic Storage

When IBM announced the random access magnetic disk storage system RAMAC 305 in 1957, it was hailed as a major break-through in data storage. By the early 1960s engineers realized that within a decade or so the system would not be able to achieve the higher areal density needed to meet the ever increasing demand for greater storage capacity. The limitation was that the hand-wound magnetic head could not be made any smaller to further increase the areal density on the discs. Many proposals were made and patents filed for small heads, but the technology to produce the required miniature 3-D structures did not exist.The first break-through came when we demonstrated that it is possible to electroplate the 3 µm thick, precise patterns of copper and permalloy required for a magnetic head through a photoresist mask on a thin, conductive seed layer. This was followed by exploratory investigations to achieve the required magnetic material properties of the metallic alloys and the invention of appropriate plating tools to build the head structures. Working side by side with the design engineers, functional requirements of the head could be balanced against fabrication process capabilities to produce a testable device.Our presentation will describe the structure of the inductive read/write heads, MR read-only heads and integrated MR read/inductive write heads. We will show that viable heads would not have been possible without several studies and inventions relating to plating solution chemistry, processing, materials and very uniform, high intensity, reproducible agitation in plating tools. Furthermore, all the process steps had to be carefully chosen to make sure no process step damaged any of the previously fabricated structure or interfered with subsequent steps. We were learning process integration before that concept even had a formal name. Once the prototype heads were built at the Yorktown Research lab and accepted for IBM’s next generation storage system, the next step was to design and build a pilot line in San Jose, IBM’s manufacturing site for magnetic storage. Electrochemical processes with the precision required for the thin film head had never before been run on a production line. Establishing the line required frequent visits to San Jose and often daily phone contact with their engineers. Furthermore, several of the engineers who were hired to run the San Jose line spent their first year with IBM in Yorktown doing research related to head fabrication, thus facilitating the transfer of this knowledge to San Jose.The five prong approach that prevailed from the first prototype to the final product was to concurrently develop the fabrication tools and to engage in studies related to the materials, the process, process control and process integration. Our preference was to use concrete data wherever possible, but to make the best engineering judgment if such data was not available. Studies were carried just far enough to obtain the information required to control the process and build the head. When time permitted, or if new problems surfaced, we could further pursue these studies. Where problems could be clearly defined and did not need head building capability, we tried to get professors and students interested in working on them.We have demonstrated that even in the absence of a full set of concrete data it is possible to build a relatively complex device by using the available information in combination with the best engineering judgment and then coming back to refine the technology into a full-fledged manufacturing process with all the necessary controls for optimum mass production.When the RAMAC 305 was first introduced, the disk size was 24 inches in diameter and the density of magnetic recording was 2 kilobits/in2. Today the disk size may be as small as two inches in diameter and the density is approaching a trillion bits per square inch – an increase of nearly 6 orders of magnitude in 50 years. In the same time, the cost of storage has dropped by 6 orders of magnitude. The successful use of electrochemistry in building the thin film head has underscored the importance of this field in both science and engineering. Electrochemical technology today is treated as a desirable fabrication approach in silicon chip fabrication, packaging, chip package attachment and MEMS. The thin film head has been a key factor in enabling the computers that now play a vital role in every aspect of our lives.

Hard disk drive thin film head manufactured using nanoimprint lithography

The lithographic requirements for the thin film head (TFH) industry are comparable to the semiconductor industry for certain parameters such as resolution and pattern repeatability. In other aspects such as throughput and defectivity, the requirements tend to be more relaxed. These requirements match well with the strengths and weaknesses reported concerning nanoimprint lithography (NIL) and suggest an alternative approach to optical lithography. We demonstrate the proof of concept of using NIL patterning, in particular Jet and Flash™ Imprint Lithography (J-FIL™) (Imprio, Jet and Flash Imprint Lithography, and J-FIL trademarks are the property of Molecular Imprints, Inc.), to build functional TFH devices with performance comparable to standard wafer processing. An Imprio™ 300 tool from Molecular Imprints, Inc. (MII) was modified to process the AlTiC ceramic wafers commonly used in the TFH industry. Templates were produced using commercially viable photomask manufacturing processes and the AlTiC wafer process flow was successfully modified to support NIL processing. Future work is identified to further improve lithographic performance including residual layer thickness uniformity, wafer topography, NIL→NIL overlay, and development of a large imprint field that exceeds what is available in optical lithography.

(Invited) Thin Film Magnetic Heads - Early Inventions and Their Ongoing Impact on Magnetic Storage and on Electrochemistry

Although many researchers in the 1960s hoped to use LSI techniques to batch fabricate magnetic read/write heads for data storage, building these devices entailed a much different set of requirements than LSI was addressing in circuit chip fabrication. Electroplating through a mask proved to be the way to pattern the magnetic elements and copper conductors of a thin film head, but this technology had to be integrated with a host of additional inventions to manufacture the device. This paper outlines the key inventions that had to be made as the head evolved from a laboratory demonstration to a manufactured product. The basic processes that were used to build the first thin film heads are still used to fabricate the heads in today's magnetic storage systems. The technology has also found its way into such diverse microelectronic applications as MEMS, NEMS, electronic packaging, semiconductor chip fabrication and, more recently, solar devices. The success of electroplating as one of the key processes in manufacturing the head has put a new focus on electrochemistry in both academia and industry.

Magnetic field of thin film heads for longitudinal recording on hard disks

Analytical expressions for the scalar magnetic potential vs. variation of magnetization in the pole of a thin-film magnetic head, pole dimensions, and the horizontal and vertical pole positions relative to the plane of the hard-disk working layer were established. Expressions for the magnetic stray fields vs. the horizontal and vertical poles were obtained by studying the pole domain structure vs. the external magnetic field and determining the domain of magnetization variation in the pole marginal zones vs. the external field. Expressions for the write fields of the thin-film heads were established as a superposition of the pole stray fields. Examples of calculations of the write fields were given for various kinds of the thin-film magnetic heads.

Magnetization process of heat assisted magnetic recording by micro-magnetic simulation

Magnetization reversal in a uniform magnetic field and one bit recording process by a thin film head in the heat assisted magnetic recording system of TbFeCo medium are studied by using the micro-magnetic simulation and the heat equation. The Landau-Lifsitz-Gilbert equation is solved for magnetic parameters at temperatures as the time goes by. It is found that magnetization proceeds as a progressive wave, although this behaviour may not limit the recording speed. The recording bit is expanded by the thermal fluctuation. The expansion can be suppressed as the medium thickness increases, because the thermal fluctuation is small in the thick medium. So the control of the medium thickness is important very much to achieve a high-density heat-assisted recording.

The Targeting Accuracy of the CyberKnife as Measured with EBT2 film inside a Ball-Cube-II film Cassette and Head Phantom

Introduction: The CyberKnife (Accuray, Inc., Sunnyvale, California, USA) is an image-guided radiosurgical system which utilizes a compact 6-MV linear accelerator mounted on a robotic arm to deliver radiosurgery. The total system error of the CyberKnife system, as measured with an anthropomorphic head phantom containing a film holder, has been previously reported to be submillimetric. In making these prior accuracy measurements, the Ball-Cube-I was used. However, a new design, the Ball-Cube-II, which uses a different kind of pre-cut films, has recently become available. In this study, we investigate the use of this device for measuring the total system accuracy of the CyberKnife. Methods: The Ball-Cube-II film cassette is a radiosurgical quality assurance (QA) tool. Similar to the existing Ball-Cube-I design, the Ball-Cube-II holds two pieces of notched radiochromic (www.gafchromic.com) film that are placed orthogonally within the film cassette. There are holes and pins in the film Ball-Cube-II cassette and holes in the EBT2 film, allowing the film to fit tightly, thus minimizing movement of the film with respect to the film cassette. The ball cube is then placed within an anthropomorphic phantom. The method for determining the localization accuracy of the CyberKnife System is similar for both film cube designs. More specifically, the spatial coordinates for the centroid of the planned dose distribution is compared with the centroid of the dose actually delivered. Results: Using the Ball-Cube-I with MD-55 film, and the head phantom, the total accuracy measured was 0.34 +/- 0.17 mm. While using the ball-cube II with EBT2 film, the total accuracy measured was 0.45 +/- 0.09 mm. Conclusions: The ball-cube-II restricts movement of the film inside the film cube, and thereby reduces the uncertainty of film placement within the cube. This design has the potential to more precisely determine the accuracy of the CyberKnife system. The accuracy of the CyberKnife using film cube with the head phantom was measured to be between 0.34 and 0.45 mm.

Paradigm Shifts in Electronics Enabled by Electrochemical Micro/Nano Processing

Advances in electronic materials, processing technologies, and integration schemes have resulted in phenomenal miniaturization of electronic components. Since the development of through-mask plating for thin film heads in the1960s and 1970s, an enormous amount of industrial and academic R effort has positioned electrochemical processing among the most sophisticated processing technologies employed in the microelectronics industry today. Electrochemical processing has thus become an integral part of advanced wafer processing and an enabling technology for nanofabrication. In this review we begin with a brief discussion of the phenomenal advances in IC based electronics and Moores law as indicators of the paradigm shifts in microelectronics. We then highlight the important role played by electrochemical processing in the electronics industry. A detailed discussion of the dual Damascene plating technology and electroplated C4 technology form the key elements of the review. Finally, the challenges and opportunities offered by these technologies in extending Moores law are discussed. Keywords: Lead-free flip-chip interconnect technology, Chip-package interconnect, Electrochemical mechanical planarization, Electropolishing, Electroless capping, Chip metallization, Moore's law, Integrated circuit, Electrochemical processing

A longitudinal 3-dimensional size and shape comparison of untreated Class I and Class II subjects

The invention of the Broadbent-Bolton cephalometer in 1925 made possible the collection of 3-dimensional data from biorthogonal plain film head radiographs. The objective of this study was to compare longitudinal changes in the shape and size of craniofacial structures between 16 untreated Class II Division 1 girls and 16 untreated Class I Bolton girls. Procrustes analyses were used to compare differences in 30 cephalometric landmarks that were 3-dimensional. The same methods were also used to analyze changes of 4 subsets of landmarks (maxilla, mandible, midface, and cranial vault). Comparisons included shape and size differences between adjacent age groups at ages 6, 11, and 15 in the Class II sample as well as between the Class I and Class II samples at each age. Overall, the craniofacial complex underwent continuous shape change from ages 6 to 15 in both samples. In the Class II sample, the smallest contribution to craniofacial shape change was seen for the mandibular landmarks between ages 6 and 11. Compared with the Class I sample, the Class II sample had (1) a longer facial pattern, (2) the smallest mandibular shape difference at age 6 and the largest at age 15, and (3) more protrusive maxillary landmarks at all ages compared with the Class I sample. The Class II sample also had the largest change in size from ages 11 to 15 (6.5%), whereas the Class I sample showed the greatest size change (10.5%) from ages 6 to 11. Clinically significant size and shape differences were observed during growth and development between Class II and Class I subjects in this sample.

Magnetic Recording Simulation of Thermally Stabilized Recording Media with a thin Film Head

The decay of the recorded magnetization due to the thermal fluctuation has become one of the most important problems to be overcome in the technology of high density magnetic recording. In this paper, a self-consistent 2D read/write simulation based on the Poisson equation by a finite element method(FEM) is performed on a system of an AFC medium and a thin film head by using an extended Stoner-Wohlfarth(SW) model for the recording layers, where the switching rate of each SW particle at finite temperatures is taken into account by using the Neel-Arrhenius law and the master equation.

Correlation of domain pattern and high-frequency response in pole-tip of inductive thin film head

The high frequency response of the soft magnetic pole tip in the thin film inductive head is crucial for the noise analysis of computer hard disk. A micromagnetic model is established in a mesoscopic soft magnetic thin film to analyze the domain pattern as well as the initial permeability in a wide frequency range from 10MHz to 18GHz. The simulated domain patterns in the pole tip, a vortex- and ladder-type, are chosen as the initial conditions for the high-frequency response studies. The scaling law of the permeability is analyzed at different amplitudes of the alternating external magnetic field. It is found that in the ladder-type domains the high frequency response is much better than that in the vortex-type domains, which agrees with experiment. A simplified explanation of the simulation result is discussed based on the analysis of the nonlinear Landau–Liftshitz equation.

Studies of Deep-Submicrometer Ultranarrow-Track Recording by Composite Simulation Models

This paper presents an analysis of the signal and noise in deep-submicrometer ultranarrow-track disk recording by composite simulation models, including the micromagnetics in longitudinal media and giant magnetoresistive (GMR) multilayers and the surface finite-element methods for inductive thin film heads and GMR head shields. The analysis assumes that the linear density of the recording process is in a range of 57 to 1200 kilo-flux changes per inch (kfci) and the width/gap ratio of the write head is between 4 and 2, corresponding to current industry practice. The first to fifth harmonics of all-one signals are found by the simulated spectrum. The signal and noise at different track densities and linear densities are analyzed by the harmonics in the spectrum. The composite heads in the disk recording system with widths 160, 240, and 320 nm are evaluated by the signal-to-noise ratio at a linear density around 1000 kfci.

Read/write simulation of thermally stabilized magnetic recording media with a thin film head

In order to study the thermal stability of an antiferromagnetically coupled medium and a keepered one with a soft magnetic underlayer, a finite element read/write simulation based on the Poisson equation is performed on the 2D model of the medium and a thin film head system. The model used for the recording layer is a Stoner–Wohlfarth model extended at finite temperatures. As a result, it is found that both media have high thermal stability compared with the conventional medium.