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An approach to fabrication of a patterned magnetic recording medium for next generation data storage systems is presented. (Co/Pd)n magnetic multilayers are evaluated as candidates for patterned medium materials for their high and easily controllable magnetic anisotropy. The multilayer films deposited on a Ta seed layer enable high intergranular exchange coupling—an essential feature of a patterned magnetic recording medium. The quality of (Co/Pd)n superlattices was optimized via deposition conditions and monitored using low-angle x-ray diffraction. An estimated in-plane (hard-axis) magnetization saturation field in excess of 40 000 Oe was observed. Vertical (easy-axis) hysteresis loops for as-deposited continuous magnetic multilayers exhibited a low coercivity of 930 Oe, indicating highly uniform (magnetically) films with weak domain wall pinning. Ion-beam proximity lithography was used to pattern magnetic multilayers into 43 nm islands on a 135 nm pitch. Following patterning, easy-axis coercivity increased nearly 15-fold to 12.7 kOe.

Magnetic force microscopy (MFM) is a widely used form of scanning probe microscopy (SPM) that is used for obtaining a magnetic image from a surface with nanoscale resolution. Currently, the resolution of MFM is limited to approximately 20 nm due to the long-range nature of magnetic interactions between the MFM probe's tip and the magnetic medium. This paper describes an optimal signal processing solution to the problem of achieving high resolution MFM with the goal of significantly exceeding the level at which MFM metrology currently performs, thus providing metrologists with a means of resolution increase that is believed will enable, for example, the rapid development of high-density magnetic recording media (>100 Gbit in−2). This is achieved by using focused-ion beam trimming of a conventional tip to create a probe tip of predictable magnetic characteristics and then, provided that the sample could be approximated as a thin-film, using knowledge of this tip's sensitivity field for performing a deconvolution on the measured signal to better estimate the magnetic state of the surface under study. Stated differently, as the MFM measured signal is modelled as the convolution of the magnetized surface and the tip's sensitivity field, we exploit knowledge of the tip's properties to increase the resolution of the MFM image. Details of the deconvolution approach as well as images resulting from this processing are the focus of this paper.

In this tutorial, focused-ion-beam (FIB)-based fabrication is considered from a very unconventional angle. FIB is considered not as a fabrication tool that can be used for mass production of electronic devices, similar to optical and E-beam—based lithography, but rather as a powerful tool to rapidly fabricate individual nanoscale magnetic devices for prototyping future electronic applications. Among the effects of FIB-based fabrication of magnetic devices, the influence of Ga+-ion implantation on magnetic properties is presented. With help of magnetic force microscopy (MFM), it is shown that there is a critical doze of ions that a magnetic material can be exposed to without experiencing a change in the magnetic properties. Exploiting FIB from such an unconventional perspective is especially favourable today when the future of so many novel technologies depends on the ability to rapidly fabricate prototype nanoscale magnetic devices. As one of the most illustrative examples, the multi-billion-dollar data storage industry is analysed as the technology field that strongly benefited from implementing FIB in the above-described role. The essential role of FIB in the most recent trend of the industry towards perpendicular magnetic recording is presented. Moreover, other emerging and fast-growing technologies are considered as examples of nanoscale technologies whose future could strongly depend on the implementation of FIB in the role of a nanoscale fabrication tool for rapid prototyping. Among the other described technologies are 'ballistic' magnetoresistance, patterned magnetic media, magnetoresistive RAM (MRAM), and magnetic force microscopy.

A focused ion beam (FIB) process can be utilized not only for etching but also for deposition at dimensions in the nanoscale range. In this paper, a ring-type magnetic head with dimensions in the nanoscale range was fabricated via FIB etching followed by FIB deposition of non-magnetic tungsten into the etched trenches. As a result, magnetic pole tips each with a cross-section as narrow as 140 × 60 nm2 and with a length as tall as 500 nm were protected and supported from all the sides. Direct observation of the 'easy' magnetization switching via magnetic force microscopy verified that favourable magnetic properties were preserved during such nanoscale processing.

Focused ion beam (FIB) applications in the field of nanoscale probe recording are explored. A detailed description of how to use FIBs for trimming longitudinal and perpendicular magnetic recording and playback devices to dimensions of less than 100 nm is presented. An experiment was conducted to demonstrate that the magnetoresistive property of a read element, e.g. a giant-magnetoresistive sensor, strongly depends on the focused ion current and the beam accelerating voltage.

The inaugural conference on Nanoscale Devices and System Integration (NDSI-2004) was held in Miami, Florida, 15-19 February, 2004. The focus of the conference was `real-life' devices and systems that have recently emerged as a result of various nanotechnology initiatives in chemistry and chemical engineering, physics, electrical engineering, materials science and engineering, biomedical engineering, computer science, robotics, and environmental science. The conference had a single session all-invited speaker format, with the presenters making the `Who's Who in Nanotechnology' list. Contributed work was showcased at a special poster session. The conference, sponsored by the Institute of Electrical and Electronics Engineers (IEEE) and the US Air Force, and endorsed by Materials Research Society (MRS), drew more than 160 participants from fourteen countries. To strengthen the connection between fundamental research and `real-life' applications, the conference featured a large number of presenters from both academia and industry. Among the participating companies were NEC, IBM, Toshiba, AMD, Samsung, Seagate, and Veeco. Nanotechnology has triggered a new wave of research collaborations between researchers from academia and industry with a broad range of specializations. Such a global approach has resulted in a number of breakthrough accomplishments. One of the main goals of this conference was to identify these accomplishments and put the novel technology initiatives and the emerging research teams on the map. Among the key nanotechnology applications demonstrated at NDSI-2004 were carbon-nanotube-based transistors, quantum computing systems, nanophotonic devices, single-molecule electronic devices and biological magnetic sources. Due to the unprecedented success of the conference, the organizing committee of NDSI has unanimously chosen to turn NDSI into an annual international nanotechnology event. The next NDSI is scheduled for 4-6 April, 2005, in Houston, Texas. Details can be found on the conference web site at http://www.nanointernational.org. This special issue of Nanotechnology features selected papers from NDSI-2004.

A bit patterned magnetic array based on Co/Pd magnetic multilayers with a binary perpendicular magnetic anisotropy distribution was fabricated. The binary anisotropy distribution was attained through angled helium ion irradiation of a bit edge using hydrogen silsesquioxane (HSQ) resist as an ion stopping layer to protect the rest of the bit. The viability of this technique was explored numerically and evaluated through magnetic measurements of the prepared bit patterned magnetic array. The resulting graded bit patterned magnetic array showed a 35% reduction in coercivity and a 9% narrowing of the standard deviation of the switching field.