Cock Lodder | University of Twente (original) (raw)
Papers by Cock Lodder
AIP Conference Proceedings, 2003
ABSTRACT The numerous, proprietary file formats for Scanning Probe Microscopy (SPM) have caused p... more ABSTRACT The numerous, proprietary file formats for Scanning Probe Microscopy (SPM) have caused problems in the field of both off-line quantitative, data analysis and comparison, as well as long-term archiving of measurement results. Because of the eminent roll SPM's are playing in the multidisciplinary scientific world of today, an open, XML-based, standard SPM data format, called Scanning Probe Microscopy Markup Language (SPML) is proposed. XML (eXtensible Markup Language) has proven to be well applicable for standardized, structured, scientific data formats in many other disciplines. The structure of SPML will be explained briefly. The versatility of SPML as well as the possibilities of documenting, publishing, searching and exchanging SPM-data will be shown in examples. This paper gives an overview of the proposed data format, while the complete description can be found at http://spml.net.
Magnetic Storage Systems Beyond 2000, 2001
In this paper, a new design of dedicated magnetic force microscope (MFM) cantilever is presented.... more In this paper, a new design of dedicated magnetic force microscope (MFM) cantilever is presented. In this design, the cantilever and the magnetic tip are realized in an integrated manufacturing process. The use of silicon micromachining techniques enables batch fabrication of several hundred cantilevers on a single Si wafer. The magnetic tip is prepared by deposition of magnetic material on a free standing silicon nitride layer. The width and thickness of the magnetic tip are defined by the thickness of the silicon nitride layer and the magnetic layer respectively. The length of the tip is lithographically defined. This enables us to realize very thin, high aspect ratio magnetic tips with excellent control over the tip dimensions.
Journal of Physics D: Applied Physics, 2005
ABSTRACT We present our results on the development of magnetic sensors for application in magneti... more ABSTRACT We present our results on the development of magnetic sensors for application in magnetic probe recording. Successful writing experiments on a magnetic medium with perpendicular anisotropy show that magnetic domains of 130 nm can be reversed in a heat-assisted process. For reading purposes we propose a magnetoresistive sensor. The optimization of the shape of the sensor was performed using micromagnetic simulations with the requirement that the sensor has to be capable of both read and write operations. At this stage, the experimental realization of the sensor was carried out at a wafer-base level. The fabrication technique consists of a combination of optical lithography and focused ion beam etching.
Journal of Magnetism and Magnetic Materials, 1988
The angular dependences of the H,. H,, orientation ratio (OR), hysteresis loss (IV,) as a paramet... more The angular dependences of the H,. H,, orientation ratio (OR), hysteresis loss (IV,) as a parameter of the applied field and the dependence of the distribution of hysteresis loss (AW,,) on the applied field have been systematically investigated with respect to the degree of Cr segregation in CoCr films. Starting with synthetical investigation of the microscopic phenomena and macroscopic measurement results, we attempt to explain the correlation of the segregated microstructure to the magnetization reversal mechanism in CoCr films. As the substrate temperature (T,) increases from RT to 300 o C, leading to an increase in the degree of the separation in CoCr films, all the M,, H,, OR, anisotropy constant and nucleation field (H,) obviously increase. On the contrary, as T, increases the stripe-domain configuration will gradually disappear. There is a continuous transition between the domain-wall motion and rotational reversal, depending on the T, and the heat-treatment. Combining the TEM observation of segregated microstructure with the measured results of magnetic behaviour, the magnetization reversal for a partly segregated film is considered as the superposition of the domain-wall with perpendicular and in-plane orientation of the magnetization. However, in the case of a fully segregated film, it is thought to be the superposition of a cos type of perpendicular incoherent rotation reversal with in-plane domain-wall motion. Based on the above assumption, it was found that the measured angular dependences of the coercivity are in good agreement with the calculated ones for partly and fully segregated CoCr films. Experimental data show that the annealing treatment is favourable for improving the perpendicular recording properties in CoCr films.
AIP Conference Proceedings, 2003
ABSTRACT The numerous, proprietary file formats for Scanning Probe Microscopy (SPM) have caused p... more ABSTRACT The numerous, proprietary file formats for Scanning Probe Microscopy (SPM) have caused problems in the field of both off-line quantitative, data analysis and comparison, as well as long-term archiving of measurement results. Because of the eminent roll SPM's are playing in the multidisciplinary scientific world of today, an open, XML-based, standard SPM data format, called Scanning Probe Microscopy Markup Language (SPML) is proposed. XML (eXtensible Markup Language) has proven to be well applicable for standardized, structured, scientific data formats in many other disciplines. The structure of SPML will be explained briefly. The versatility of SPML as well as the possibilities of documenting, publishing, searching and exchanging SPM-data will be shown in examples. This paper gives an overview of the proposed data format, while the complete description can be found at http://spml.net.
Magnetic Storage Systems Beyond 2000, 2001
In this paper, a new design of dedicated magnetic force microscope (MFM) cantilever is presented.... more In this paper, a new design of dedicated magnetic force microscope (MFM) cantilever is presented. In this design, the cantilever and the magnetic tip are realized in an integrated manufacturing process. The use of silicon micromachining techniques enables batch fabrication of several hundred cantilevers on a single Si wafer. The magnetic tip is prepared by deposition of magnetic material on a free standing silicon nitride layer. The width and thickness of the magnetic tip are defined by the thickness of the silicon nitride layer and the magnetic layer respectively. The length of the tip is lithographically defined. This enables us to realize very thin, high aspect ratio magnetic tips with excellent control over the tip dimensions.
Journal of Physics D: Applied Physics, 2005
ABSTRACT We present our results on the development of magnetic sensors for application in magneti... more ABSTRACT We present our results on the development of magnetic sensors for application in magnetic probe recording. Successful writing experiments on a magnetic medium with perpendicular anisotropy show that magnetic domains of 130 nm can be reversed in a heat-assisted process. For reading purposes we propose a magnetoresistive sensor. The optimization of the shape of the sensor was performed using micromagnetic simulations with the requirement that the sensor has to be capable of both read and write operations. At this stage, the experimental realization of the sensor was carried out at a wafer-base level. The fabrication technique consists of a combination of optical lithography and focused ion beam etching.
Journal of Magnetism and Magnetic Materials, 1988
The angular dependences of the H,. H,, orientation ratio (OR), hysteresis loss (IV,) as a paramet... more The angular dependences of the H,. H,, orientation ratio (OR), hysteresis loss (IV,) as a parameter of the applied field and the dependence of the distribution of hysteresis loss (AW,,) on the applied field have been systematically investigated with respect to the degree of Cr segregation in CoCr films. Starting with synthetical investigation of the microscopic phenomena and macroscopic measurement results, we attempt to explain the correlation of the segregated microstructure to the magnetization reversal mechanism in CoCr films. As the substrate temperature (T,) increases from RT to 300 o C, leading to an increase in the degree of the separation in CoCr films, all the M,, H,, OR, anisotropy constant and nucleation field (H,) obviously increase. On the contrary, as T, increases the stripe-domain configuration will gradually disappear. There is a continuous transition between the domain-wall motion and rotational reversal, depending on the T, and the heat-treatment. Combining the TEM observation of segregated microstructure with the measured results of magnetic behaviour, the magnetization reversal for a partly segregated film is considered as the superposition of the domain-wall with perpendicular and in-plane orientation of the magnetization. However, in the case of a fully segregated film, it is thought to be the superposition of a cos type of perpendicular incoherent rotation reversal with in-plane domain-wall motion. Based on the above assumption, it was found that the measured angular dependences of the coercivity are in good agreement with the calculated ones for partly and fully segregated CoCr films. Experimental data show that the annealing treatment is favourable for improving the perpendicular recording properties in CoCr films.