ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Microscopic studies of the magnetization-reversal process in Co-alloy thin films (abstract) (1990)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 67 (1990), S. 4713-4713 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A quantitative study of the microscopic magnetization-reversal process in 250-A(ring) thick Co, Co90Pt10, and Co88Cr12 films deposited on top of a 250-A(ring)-thick Cr layer has been carried out. The entire structure was on a SiN membrane to allow ease of observation in the transmission electron microscope (TEM). The magnetization-reversal process was studied by using an electromagnet to saturate the film in one direction; the applied field was then reversed until the sample reached a magnetization state between +Mr and −Mr; the field was then reduced to zero and the sample taken to the TEM for observation of the resulting magnetic structure using Fresnel and DPC Lorentz microscopy.1 This process was repeated for a number of reversal fields ranging from zero to the loop closure field. This study shows that as the reversal field was increased from zero towards the coercivity, the magnetization dispersion, i.e., the range of angles between the local magnetization and the original saturation direction, increased. The local magnetization direction varied markedly from one region of the film to the next, indicating that it is strongly tied to the local anisotropy of the film. Once the steep part of the B-H loop is reached, small reversed regions are nucleated. These reversed regions consume the entire film by continued growth and nucleation as the reverse field is increased. The nucleation occurs at the same site when the magnetization is cycled around the B-H loop. This indicates that the local anisotropy determines the sites in which critical nuclei are formed in a given applied field. The boundary between the switched and unswitched regions consists of a complex magnetization vortex structure. Once the entire film has been switched, the local magnetization dispersion decreases as the reverse field is increased. Comparison of the results among the Co-alloy films will be discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.344809
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Enhanced coercivity in CoPtCr thin film media using CrV underlayer (abstract) : 37th Annual conference on magnetism and magnetic materials (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 5579-5579 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: As the areal density of thin magnetic media continues to increase1,2 and aims toward 10 gigabits/in2, the future media's magnetic properties and recording performance such as the coercive force and signal to noise ratio need to increase substantially.3 In this paper we report the use of a chromium vanadium underlayer as a method to control the microstructure and enhance the coercivity of CoPtCr media. To study the effect of the underlayer composition on microstructure and magnetic properties, CrV-alloy/CoPtCr structures were fabricated with CrV-alloy concentration ranging from pure Cr to pure V. The magnetic media target concentrations were Co75Pt12Cr13, Co74Pt9Cr17, and Co80Pt3Cr17. We observed that the coercivity increases as the vanadium concentration in the CrV alloy increases and peaks at 50 at. % V. The Cr50V50/CoPtCr yielded between 30% and 40% higher coercivity values than Cr/CoPtCr for the same thickness of underlayer and magnetic layer. The microstructures (by TEM) of the CrV underlayer and the CrV/CoPtCr show that the underlayer grains are largest at 50 at. % V and that the CoPtCr grains mimic those of the underlayer. There is also considerable amount of epitaxy between the (200) planes of the CrV and (110) planes of the CoPtCr. The increase in grain size and preferred orientation in the polycrystalline magnetic field is believed to affect the coercivity by reducing the magnetostatic coupling and increasing the magnetocrystalline anisotropy.4
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.353657
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Effects of dc bias on the kinetics and electrical properties of silicon dioxide grown in an electron cyclotron resonance plasma (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 70 (1991), S. 3301-3313 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Thin (3–300-nm) oxides were grown on single-crystal silicon substrates at temperatures from 523 to 673 K in a low-pressure electron cyclotron resonance (ECR) oxygen plasma. Oxides were grown under floating, anodic or cathodic bias conditions, although only the oxides grown under floating or anodic bias conditions are acceptable for use as gate dielectrics in metal-oxide-semiconductor technology. Oxide thickness uniformity as measured by ellipsometry decreased with increasing oxidation time for all bias conditions. Oxidation kinetics under anodic conditions can be explained by negatively charged atomic oxygen, O−, transport limited growth. Constant current anodizations yielded three regions of growth: (1) a concentration gradient dominated regime for oxides thinner than 10 nm, (2) a field dominated regime with ohmic charged oxidant transport for oxide thickness in the range of 10 nm to approximately 100 nm, and (3) a space-charge limited regime for films thicker than approximately 100 nm. The relationship between oxide thickness (xox), overall potential drop (Vox) and ion current (ji) in the space-charge limited transport region was of the form: ji ∝ V2ox/x3ox. Transmission electron microscopy analysis of 5–60-nm-thick anodized films indicated that the silicon-silicon dioxide interface was indistinguishable from that of thermal oxides grown at 1123 K.High-frequency capacitance-voltage (C-V) and ramped bias current-voltage (I-V) studies performed on 5.4–30-nm gate thickness capacitors indicated that the as-grown ECR films had high levels of fixed oxide charge ((approximately-greater-than)1011 cm−2) and interface traps ((approximately-greater-than)1012 cm−2 eV−1). The fixed charge level could be reduced to ≈4×1010 cm−2 by a 20 min polysilicon gate activation anneal at 1123 K in nitrogen; the interface trap density at mid-band gap decreased to ≈(1–2)×1011 cm−2 eV−1 after this process. The mean breakdown strength for anodic oxides grown under optimum conditions was 10.87±0.83 MV cm−1. Electrical properties of the 5.4–8-nm gates compared well with thicker films and control dry thermal oxides of similar thicknesses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.349264
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    On the switching characteristics of Co and CoPtCr thin films (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 7731-7734 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have studied the influence of intergranular magnetic coupling on switching characteristics in Co and CoPtCr thin films. The strength of the intergranular interactions was varied by changing the sputtering pressure and film or underlayer thickness. For each sample we have measured the deviation δM from the behavior expected for noninteracting single-domain particles and correlated the results to the magnetic layer and under layer thickness and to the microstructure of the recording film. We show a correlation between δM and the strength of magnetic coupling. Where similar magnetic parameters allow a comparison, we find a correlation between media noise and the trend in δM.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347549
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Status of development of ECR ion sources at Grenoble (invited) : Proceedings of fifth international conference on ion sources (1994)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 65 (1994), S. 1051-1056 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: This article gives a short summary of the performances of the electron cyclotron resonance ion sources (ECRIS) so far built by the Grenoble laboratory; emphasis is given to the high B field Caprice source, a compact in size source delivering high charge states and high intensities. Both the continuous regime of operation, and the pulsed regime having performances enhanced by the afterglow effect, as well as other noticeable effects, are surveyed. The next part of the article deals with the analysis of the data and our present understanding of the ECRIS behavior. At last the present trends of development of ECRIS are examined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1145113
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A model of defect-mediated transport through amorphous membranes (1992)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 96 (1992), S. 3177-3182 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We introduce a class of membrane diffusion models which consists of an impermeable slab punctured by transmembrane pores which are constructed by continuous random-walk algorithms. These formally infinite tortuosity models closely resemble low tortuosity models in their steady-state flux and total transient uptake. The sharpest contrast between random and homogeneous membranes is in the stretched exponential (subdiffusive) decay [exp(−tα), α=1/2] of the transient diffusive flux for the random-pore models vs simple exponential decay [exp(−t)] for homogeneous membranes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.461961
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Experimental study of the beam divergence from a broad-beam electron cyclotron resonance ion source : International conference on ion sources (1990)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 61 (1990), S. 291-293 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Various factors affecting divergence of an ion beam extracted from a broad-beam electron cyclotron resonance ion source are studied. The source has three graphite grid extraction optics providing an 18-cm ion beam. A simple apparatus and method is used to investigate the beam divergence as a function of source pressure, magnetic field, microwave power, beam energy, and suppression voltage. We discovered that the beam divergence ranges from ±4° to ±8°. We also noticed that, considering a 10% experimental error, suppression voltage does not strongly affect the beam divergence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1141325
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Ultrathin oxide-nitride-oxide films (1990)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 57 (1990), S. 1248-1250 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: It is demonstrated that the thickness limit of a thin nitride film which can withstand reoxidation is reduced to about 3.5 nm when it is deposited in situ on a thin-deposited oxide film. The deposited oxide apparently provides a better surface for nitride nucleation and initial growth. Using this finding an oxide-nitride-oxide (ONO) film as thin as 4.6 nm was fabricated and shown to have good electrical properties and low defect density. The current leakage through the film was close to the acceptable limit in dynamic-random-access-memory technology. It was also found that electron trapping is substantially higher in ONO films produced by reoxidation than in films having a top deposited oxide.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.103499
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Fluorescence energy transfer between two triple helix-forming oligonucleotides bound to duplex DNA (1994)
    s.l. : American Chemical Society
    Biochemistry 33 (1994), S. 15321-15328 
    Details
    ISSN: 1520-4995
    Source: ACS Legacy Archives
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/bi00255a013
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    X-ray reflectivity measurements of the expansion of carbon films upon annealing (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 59 (1991), S. 2100-2102 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Measurements have been made of the x-ray reflectivity from ultrathin, amorphous carbon films both before and after annealing. Analysis of the x-ray results indicates that annealing causes an increase in film thickness with a corresponding decrease in density. Such behavior is uncharacteristic of amorphous thin films and is interpreted as being due to changes in the interatomic bonding associated with transition to a more graphitic microstructure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.106093
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...