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The change of an internal stress in each layer consisting of AZO/Cu/Mo multilayer thin films with temperature were experimentally measured for the first time by using a grazing incidence X-ray diffraction (GI-XRD). These measurements were performed by taking account of relatively large difference of the total reflection values among AZO(2 wt%Al2O3 + ZnO), Cu and Mo, so that the structural properties of each layer of AZO/Cu/Mo tri-layer can be measured in turn by changing an incident angle of a GI-XRD. It was found that the stress mode of AZO, Cu and Mo single layers were compression, tension and tension, respectively. Their stress mode does not change even after forming multilayers and with successive anneals up to 400 °C. The internal stress of each layer in multilayer tends to decrease to accommodate each thermal mismatch among AZO, Cu and MO layers. It was demonstrated that the internal stress in each layer of the multilayer thin films had been measured with a nondestructive method by using a GI-XRD.

The internal stresses in an each layer of multiple layer's film (AZO, Cu, and Mo) has been measured experimentally using grazing incidence X-ray diffraction. This was performed utilizing the difference of total reflection values between consisting layers so as to be able to measure the each internal stresses in turn by the GISD.

Occupational exposure to anticancer drugs may increase the risk of cancer and the risk of miscarriage and stillbirth, and cause other adverse events such as hypersensitivity reactions, skin/mucous reactions, and digestive symptoms. Several studies have investigated the use of closed-system drug-transfer devices (CSTDs) to reduce the environmental pollution by hazardous drugs. However, few reports have verified whether CSTDs contain the hazardous drugs within the vials. The BD PhaSealTM System is a CSTD that is frequently used in Japan. However, the fit of each anti-cancer drug vial has not been investigated. We investigated the fit of 71 major anti-cancer drug vials and protectors released and frequently used in Japan by means of a pressure compatibility test that we developed. The pressure compatibility test involved attaching a three-way stopcock to a Luer lock syringe and attaching an injector in line with the syringe. The pressure tubing was connected to the other side of the three-way stopcock and connected to the pressure inlet of the pressure gauge. The pressure in the anti-cancer drug vial was raised to 100 kPa and connected/disconnected repeatedly. If the pressure fluctuation during the 10th connection was within 6%, it was defined as "no change", and the compatibility of the protector and the vial was evaluated. The median pressure reduction rates at the 10th connection ranged from -1.98% to -4.95%. All drugs surveyed had an error rate within 6%. The BD PhaSealTM Protector was shown to be compatible with the 71 anti-cancer drugs we surveyed.

Background Many reports support the use of closed system drug transfer devices (CSTDs) to protect against exposure to hazardous drugs during their preparation. However, leakage may occur if the CSTD fails to maintain hermeticity when fitted into the vial. Our aims were to devise a measure to prevent HD exposure and to develop a test method to verify CSTD function when a BD PhaSeal™ protector is used in HD preparation. Methods We selected the BD PhaSeal™ System, which is the most commonly used CSTD device in Japan. The sealability of the BD PhaSeal™ protector and vial is considered to be due to the hermeticity of the protector and the rubber stopper of the vial. We constructed a protector with a damaged sealing rim and monitored the pressure fluctuation 10 times when the BD PhaSeal™ injector was connected to the pressurized vial. Results The reduction in pressure of the protector in the group without a damaged sealing rim was 5%, while that in the group with the damaged sealing rim was 84.9%. Conclusion It was suggested that leakage occurred through the gap between the protector and the rubber stopper when using a vial that was not in close contact with the sealing rim. In this study, we developed a test that can be easily used to verify the compatibility of the BD PhaSeal™ protector and a vial in the clinical setting. Thus, when new hazardous drugs are being prepared, these measures can be taken to ensure that the risk of exposure is reduced or eliminated.

Annealing behavior of dilute Cu-X alloys (adding element X = transition metal and rare-earth metal with less than 3 at %) was investigated in terms of resistivity, internal stress, grain growth and hillock formation. The resistivity increases with addition of impurities regardless of kinds of adding elements. Generally, resistivity starts to decrease on annealing above 200 °C. Among present Cu dilute alloys, Sn addition shows the lowest resistivity 2.5 μΩcm on annealing at 400 °C. However, compared with a pure Cu film, salient grain growth of present dilute alloys does not takes place even at temperatures above 300 °C , where the grain size is nearly the same as that of as-deposited films. In-situ surface observation using an atomic force microscope (AFM ) revealed that hillocks did not grow on cooling stage (under tension), but started to form on heating stage (under compression). The scanning electron microscopy (SEM) observation of hillocks thus formed in present dilute alloy films shows that the external appearance of these defects was quite different from those observed in Al and Al alloy films. They most likely grow with a preferential crystal plane, not irregular growth like Al and Al alloy films. The internal stresses in most of the present as-deposited dilute Cu alloy films were nearly zero or compression of –25 to –100MPa, and upon annealing, they started to increase in tensile manner due to thermal stresses induced by the mismatch of the thermal expansion between substrates and deposited films. A large stress relaxation started to occur above 250°C, associating with a large number of hillock formation.

Administration of vitamin B12 and folic acid for 7 days prior to the administration of the first dose of pemetrexed is recommended. However, vitamin supplementation rarely is initiated less than 7 days prior to the first dose of pemetrexed. Therefore, we analyzed the safety of pemetrexed with vitamin supplementation for less than 7 days prior to the first dose of pemetrexed.Patients were classified into 2 groups according to the duration of vitamin supplementation prior to the first dose of pemetrexed: group A received vitamin supplementation for 7 days or more, and group B received vitamin supplementation for less than 7 days. We analyzed adverse effects, such as myelosuppression, rash, and diarrhea, after 1 cycle of pemetrexed therapy.A total of 70 patients were administered pemetrexed; 40 patients were men and 30 were women with a median age of 64.5 years(range, 43-86 years). A total of 57 patients were classified into group A and 13 into group B; 33 patients were administered pemetrexed as a first-line treatment. Neutropenia of Grade 3 or more was observed in 4/49(8.2%)patients in group A and 2/13(15.4%)patients in group B(p=0.60). There were no significant differences in the rates of occurrence of neutropenia, rash, and diarrhea.This retrospective study indicated that patients could be safely treated with pemetrexed if vitamin supplementation is initiated for less than 7 days prior to the first administration of pemetrexed. However, further studies are needed because of a lack of statistical power and adjustment for confounding factors.

Indium tin oxide (ITO) films prepared by dc magnetron sputtering were annealed in air, vacuum, and oxygen gas atmospheres. The electrical properties and internal stresses of these annealed ITO films were systematically investigated. It was found that, among the above postannealing treatments, oxygen gas annealing significantly reduced both the resistivity and the internal stress in ITO films at fairly low temperatures of 100–150 °C. Resistivities and internal stresses as low as 7×10−4 Ω cm and 38 MPa, respectively, were obtained by annealing in oxygen gas atmosphere at 100 °C. It was also revealed that the (111) crystal orientation becomes dominant and that whole grains grow dramatically as a result of postoxygen annealing, even at 100 °C.

We investigated the effects of adding Zr or Nb to Al thin films on the structure and resistivity changes during annealing to assess the potential use for TFT-LCD (thin-film-transistor liquid-crystal displays) gate electrodes. These as-made alloy films (with 1.5-4.2 at% of added elements) show very fine grain less than 100 nm in size and mainly consist of a highly supersaturated solid solution of the Al phase. The addition of Zr or Nb to Al thin films markedly suppresses the grain growth at high temperatures (350-450°C), but thermal defects of hillocks or whiskers start to appear on the film surfaces after annealing at 250°C. It was shown that small amounts of metallic compounds of Al 3 X (X = Zr or Nb) precipitated in a supersaturated solid solution of the Al phase after annealing at 350°C, and that a large amount of added impurities still remained in the Al matrix. The resistivity of Al 98.5 Zr 1.5 alloy films showed about 5 μΩ.cm after annealing at 450°C.

The addition of either Sm or Dy rare earth metal elements to Al thin films decreases markedly the grain size of the Al matrix and largely suppresses the growth of hillock and whisker thermal defects at high temperatures (350–450°C). A large number of particles of fine metallic compounds of Al3RE (RESm or Dy) were segregated in an Al matrix, mostly at grain boundaries, after annealing at 350°C. The resistivities of the films after annealing at the above temperatures show very low values of less than about 50 nμ m, without salient formation of hillocks or whiskers on the film surfaces.

The amorphous structures of Nd 17 Fe 83 and Nd 18 Co 82 alloys with high Kerr rotation at short wavelengths were examined by means of X-ray diffraction, using dense random packing of hard sphere model analysis and polyhedron analysis. It was observed that the general local environments of NdFe and NdCo amorphous structures are very similar and that their local atomic structures are very close to those of an RETM 2 crystalline Laves phase.

Indium tin oxide (ITO) films prepared by d.c. magnetron sputtering were annealed in air, vacuum, and oxygen gas atmosphere. The electrical properties and internal stresses of these annealed ITO films were systematically investigated. It was found that, among the above post-annealing treatments, oxygen gas annealing significantly reduced both the resistivity and the internal stress in ITO films at fairly low temperatures of 100–150°C. Resistivities and internal stresses as low as 7×10-4 Ωcm and 38 MPa, respectively, were obtained by annealing in oxygen gas atmosphere at 100°C. It was also revealed that the (111) crystal orientation becomes dominant and that whole grains grow dramatically as a result of post-oxygen-annealing, even at 100°C.

The electronic structure of amorphous ${\mathrm{Co}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{B}}_{\mathit{x}}$ (x=0.17, 0.23, and 0.32) alloys were calculated to clarify their magnetism and electronic specific heat. The electronic structures were calculated self-consistently, both in the spin-polarized and paramagnetic states, by employing the most-localized linear muffin-tin orbital method together with the recursion method. B s and p states split into bonding and antibonding states, and B p states, in particular, hybridize with the tails of Co d states. The exchange splitting of Co d states decreases with increasing B content mainly because of the enhancement of the hybridization. As a result, amorphous Co-B alloys become less ferromagnetic as their B content increases. The calculated magnetic moments per Co atom are proportional to the exchange splitting of Co d states, and decrease with increasing B content. They can be satisfactorily explained by the generalized Stoner model, and agree quantitatively with the experimental data. The density of states at the Fermi level rises with increasing B content, because the highest peak of the minority Co d states shifts toward the Fermi level owing to the decrease in the exchange splitting. This explains a gradual increase in the electronic specific coefficient observed in the experiment.

The magnetic state in amorphous (${\mathrm{Co}}_{0.85}$${\mathrm{B}}_{0.15}$${)}_{100\mathrm{\ensuremath{-}}\mathit{x}}$${\mathit{X}}_{\mathit{x}}$ (X=B, Al, Si, and V) prepared by liquid quenching has been studied through the measurements of the saturation magnetization at 4.2 K, the Curie temperature, and the spin-wave stiffness constant. The electronic structure was investigated by measuring the low-temperature specific heats and ultraviolet-photoemission-spectroscopy valence-band spectra. Combining the previously reported data on amorphous (${\mathrm{Co}}_{0.9}$${\mathrm{Zr}}_{0.1}$${)}_{100\mathrm{\ensuremath{-}}\mathit{x}}$${\mathit{X}}_{\mathit{x}}$ (X=Al, Si, Cu, Ge, and Zr) alloys, we could show that the linearly temperature-dependent specific-heat coefficient ${\ensuremath{\gamma}}_{\mathit{e}\mathit{x}\mathit{p}\mathit{t}}$ in these ferromagnetic amorphous alloys reflects well the density of states N(${\mathit{E}}_{\mathit{F}}$) at the Fermi level, provided that the spin-wave stiffness constant is above about 150 meV A${\mathrm{\r{}}}^{2}$. The electron-transport properties have been discussed in detail only for those whose ${\ensuremath{\gamma}}_{\mathit{e}\mathit{x}\mathit{p}\mathit{t}}$ offers reliable information on N(${\mathit{E}}_{\mathit{F}}$). The participation of weak-localization effects has been concluded from the following: (1) the coefficient \ensuremath{\xi} of logarithmic temperature dependence of resistivity at low temperatures increases while TCR, the temperature coefficient of resistivity defined as (1/\ensuremath{\rho})(d\ensuremath{\rho}/dT), near 300 K decreases with increasing resistivity and (2) amorphous alloys with the largest values of \ensuremath{\xi} are always found near the high-resistivity limiting curve on the \ensuremath{\rho}-\ensuremath{\gamma} diagram.

The uniaxial anisotropy of Tb19Co81 and Tb19Fe81 amorphous alloy films was investigated by using X-ray diffraction analysis and measuring the magnetic anisotropy constants, Ku, on annealing at 200°C. It was revealed that, in the TbFe film investigated, the anisotropic structure was more extensively relaxed at an early stage of annealing than in the TbCo film. During this relaxation process, near-neighboor correlations changed mainly around TbTb pairs in the TbFe film, whereas they changed mainly around CoCo pairs in the TbCo film. The magnetic anisotropy decreased more rapidly in the TbFe film than in the TbCo film, reflecting this difference in the structural relaxation process.

The spin-polarized electronic structures of ${\mathrm{Gd}}_{33}$${\mathrm{Fe}}_{67}$ alloys were calculated self-consistently in both the amorphous phase and the crystalline Laves phase. The most localized linear-muffin-tin-orbital (LMTO) method together with the recursion method was employed in the amorphous phase, and the conventional LMTO method was employed in the crystalline phase. The density of states (DOS) obtained in the amorphous phase agrees well with experimental data from x-ray photoemission spectroscopy. Although there are some common features in the DOS's of the amorphous and crystalline phases, the projected DOS's are very different from each other, especially in Fe d states. This difference seems to originate from the difference in the local atomic structure between these two phases. The resultant magnetic moments in the amorphous phase are 2.0${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$ at the Fe site and 7.20${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$ at the Gd site, respectively. These values agree well with experimental data.

The spin-polarized electronic structure of an amorphous alloy was calculated in a Gd33Fe67 alloy for the first time, a result long awaited because it allows us to clarify the magnetic and magneto-optical properties. The calculated density of states of the Fe and Gd d-state show roughly a single peak structure. The resultant magnetic moment of Fe is 2.0μB, and shows good agreement with experimental value of 1.9μB. The contribution of each constituent atom to the Kerr effect is well manifested on the basis of the obtained electronic structure.

Recently, ambulatory treatment centers (ATC) are markedly increasingboth in number and scale. It is therefore important to consolidate an efficient therapeutic system. A decrease in both treatment time and waitingtime leads to not only the improvement of the quality of life (QOL) for patients but also the efficient use of personnel and running costs for medical institutions by reducingthe bed occupation rate. In ATC, 5-HT3 receptor antagonists are extensively used for high emetic risk patients. However, their high cost and prolonged treatment causes one of the problems in improvingthe efficiency of the therapeutic system when they are administered by intravenous infusion. Amongthe 4 types of 5-HT3 receptor antagonists (injections) currently available in Japan, azasetron is the only drugthat is not designated as a powerful drug and that can be administered by bolus intravenous infusion. In this study, we investigated azasetron and granisetron from the standpoint of pharmacoeconomics with a simulation model using the results of clinical studies in Japan. Accordingto the results of cost-effectiveness analysis, therapeutic and time costs per patient for azasetron 10 mgand granisetron 2 mg (calculated in consideration of both medical institutions and patients) was 8,219 and 10,193 yen, respectively. This gap was attributable to the time loss due to the difference in administration methods. The result suggests that this time loss is more significant not only for patients but also for medical staff than the loss attributable to the drugcost. Furthermore, the bolus intravenous infusion of azasetron is considered superior to the non-bolus intravenous infusion of granisetron from a pharmacoeconomic standpoint. It is desirable to choose the appropriate administration method of 5-HT3 receptor antagonists in various chemotherapy regimens for the purpose of reducingthe treatment time and promotingthe efficiency of the therapeutic system at ATCs.

Extended x‐ray absorption fine structure analysis was employed to obtain insight into the influence of structural change on the magnetic and magneto‐optical properties of Tb‐Fe amorphous films. Films made by bias sputtering show a 20% lower density and a lower apparent coordination number of Fe atoms around an Fe atom than those made by nonbias sputtering. However, their interatomic distances are unaffected by the sputtering methods. After samples made by nonbias sputtering have been annealed, the atomic distances of Fe‐Fe and Tb‐Fe tend to increase and decrease, respectively, while the apparent coordination number, N*, and the structural disorder parameter, σ, increase and decrease, respectively, in association with a large deterioration in magnetic and magneto‐optical properties. On the other hand, in the case of bias‐sputtering films, samples annealed at 200 °C show a large decrease in magnetic anisotropy, Ku, but no significant change in individual atomic distances and apparent coordination number. Ho...

The domain structure of zero magnetostrictive (Co 0.96 Fe 0.04 ) 79 Si 10 B 11 amorphous alloys was observed by both Lorentz electron microscopy and the newly developed technique of electron holography. The latter method clearly manifests, for the first time, the flow of magnetic lines of force both inside and outside an amorphous specimen.

The stress distribution of (111) textured Cu films with depth was measured by using a GIXS method. We derived the equation to correct a scattering diffraction angle with depth, measured in the GIXS Seemann-Bohlin geometry, to obtain the actual scattering angle. It was revealed after the correction of the measured scattering angles that the internal stresses of (111) grains, on the whole, tend to increase almost linearly with increasing film depth from the free surface toward the substrate. It was suggested that these results were opposite to the results of the elastic calculation reported, and hence that a large stress relaxation took place during and/or after deposition and annealing. After annealing at various temperatures, these stress distribution profiles are almost unchanged, and are simply shifted uniformly in magnitude.

This study is concerned with an oral administration of 5 mg of [1,2,4,19- 13 C 4 ,11α- 2 H ]cortisol (cortisol- 13 C 4 , 2 H 1 ) to a human subject to reliably evaluate the individual activities of two isozymes of 11β-HSD. The use of a GC–MS method allowed the simultaneous measurement of the plasma concentrations of cortisol- 13 C 4 , 2 H 1 , cortisone- 13 C 4 , and cortisol- 13 C 4 together with endogenous cortisol and cortisone. The loss of 11α- 2 H during the conversion of cortisol- 13 C 4 , 2 H 1 to cortisone- 13 C 4 by 11β-HSD2 and the regenerated cortisol- 13 C 4 from cortisone- 13 C 4 by 11β-HSD1 provided a direct and accurate means of distinguishing the activities of the two isozymes. The kinetic analysis associated with the metabolism of orally administered cortisol- 13 C 4 , 2 H 1 was of great importance in assessing the 11β-HSD activities. From a viewpoint of the chemical stability and much less pronounced kinetic isotope effect of the 13 C -label and the 2 H -labeling in the 11α-position, cortisol- 13 C 4 , 2 H 1 used in this study served as an appropriate tracer for elucidating the kinetics of the interconversion of cortisol to cortisone in man.

Direct observations using microellipsometry, Kerr microscopy, and electron backscatter diffraction are made for the first time on individual grains in the leading pole-tip region of polycrystalline ferrite MIG heads intended for narrow track ( >

Application to aluminum deposition using ion-plating method is described. This method has several superior features for generating highly (111) orientation. The origin of this orientation and surface roughness are discussed in connection with a kinetic energy of the ions. The film properties thus made were compared with those of a conventional sputtered film. The higher (111) oriented film showed high resistance against hillock formation even after annealing at high temperatures. An effect of a plasma cleaning of substrate surface was confirmed to be quite helpful for promotion of (111) preferred orientation.

Magneto‐optical recording materials with high remanent Kerr rotation at a short wavelength were successfully obtained in a trilayer form. NdCo amorphous films with an in‐plane magnetization were sandwiched between TbFeCo amorphous films with strong perpendicular anisotropy and high coercivity. The thickness of the top layer of the TbFeCo film facing an incident laser beam is less than the light‐penetration depth. Triple‐layered films [Tb18Fe49Co33 (5 nm thickness)/Nd18Co82(10 nm)/Tb18Fe49Co33(200 nm)] thus obtained show a remanent Kerr rotation angle θKr = 0.37°–0.46° at wavelength λ=400–850 nm, coercivity Hc = 2 kOe, and good square loop (Mr/Ms = 1). The figure of merit √RθK, where R is reflectivity, is 0.24–0.31 at λ=400–850 nm, which is higher than that of conventional TbFeCo amorphous films (√RθK = 0.12–0.27 at λ=400–850 nm).

The feasibility of a new method for direct overwrite with a power‐modulated laser beam under a constant external bias field Hex fixed in the same direction as an initializing field Hinit was demonstrated by means of a dynamic disk tester. TbFeCoCr amorphous films with compensation temperature (Tcomp) far below room temperature were employed, but coercivity falls below 200 Oe at 200 °C, while the saturation magnetization remains high. We found that written pits are formed by a demagnetization field Hd in the region of a weak Hex, whereas for a stronger Hex they are formed by a effective external field Heff(=Hex−Hd) fixed in the same direction as Hinit. By using a power modulation between 9 and 5 mW under a constant field of −100 Oe, we were able to demonstrate direct overwrite, although the readout carrier‐to‐noise ratio was low (18 dB).

In order to clarify the origin of the Kerr effect for a rare earth–transition metal (RE‐TM) amorphous alloy system, electronic structure calculations were performed for the first time in an amorphous system including f orbitals. Tb20Fe80 and Nd20Fe80 amorphous alloy compositions were chosen for the present work. The electronic structures were calculated by using the most localized linear muffin‐tin orbital method based on atomic sphere approximation and the recursion method. To evaluate the first excited f states of rare‐earth metals, it was assumed that the occupied f electrons were sufficiently localized in the inner core of a RE atom to be treated as core electrons. The calculated density of states for a Tb20Fe80 amorphous alloy shows good agreement with reported experimental results measured by x‐ray photoelectron spectroscopy (XPS) and inverse XPS. In particular, the unoccupied f‐state level and the hybridization property between the Tb d state and the Fe d state were well reproduced. The calculated ...

The effects of adding a third transition metal element, Co, Cu, Zr, or Ta, to Al-Nd (or Gd) alloy thin films were studied in order to investigate the changes in the film's microstructure and resistivity, and also their tendency to form hillocks or whiskers at high temperatures. The addition of Zr (or Ta), which has repulsive interactions with both Nd and Gd, to the Al-RE binary alloy films causes an increase of residual resistivity and enhances the formation of hillocks or whiskers at high temperatures. On the other hand, the addition of Cu or Co, which has attractive interactions with both Nd and Gd, results in a resistivity of less than 6 µωcm (depending on the content of added elements). Addition of either of these elements largely suppresses the growth of thermal defects after annealing at over 350 °C. The above results were explained by employing a theory of grain boundary segregation based on a chemical interaction between constituent elements of an alloy.

The resistivities of Al thin films with added Sc or Tb largely decrease at over 350 °C. They reach to 5 -7 μΩcm after annealing at 450 °C, together with the segregation of fine Al3RE (RE = Sc or Tb) metallic compounds. However, the temperatures at which resistivity starts to decrease largely are much lower for Al-SC alloy films (150 °C) than for Al-Tb ones (250 °C). Furthermore, thermal defects of hillocks or whiskers start to appear on the film surface after annealing at 200 °C and 450 °C for Al-Sc and Al-Tb alloy films, respectively. It was revealed that the further addition of Zr to these binary alloy films largely retards a large decrease of resistivities on annealing and enhances the formation of hillocks or whiskers. On the contrary, the addition of Cu to Al-Tb or Al-Sc films significantly suppresses the formation of thermal defects and shows relatively low resistivities after annealing at 350 °C.

The addition of La and Pr to Al thin films markedly decreases the grain size of the Al matrix and largely suppresses growth of thermal defects of hillocks and whiskers at high temperatures (350°C – 450°C). A large number of fine metallic compounds of Al11RE3 and/or Al3RE (RE = La and Pr) were segregated in an Al matrix, mostly at grain boundaries, after annealing at 350°C. The resistivities of the films after annealing at the above temperatures show very low values of less than 6 μωcm, without the salient formation of hillocks or whiskers on the film surfaces.

We systematically studied the effect of disk acceleration on the friction of the head-disk interface in a hard disk drive. As a result, we found that the fricuonal energy can be reduced by the way in which head passes through a region of relatively low linear speed with a relatively high acceleration. We also found that the kinetic fiictional force is independent of the acceleration, and the curve of the frictional force's dependence on linear velocity is well correlates witii the disk surface roughness or lubricant thickness. In addition, we studied the dependence of the static friction force on the spin-up spindle acceleration. The peak stiction force is strongly correlated the loading rate of the external force, especially when the contact area is wide.

The cause of the readback waveform distortion in polycrystalline ferrite metal-in-gap (MIG) heads was investigated by using a magnetic force microscope (MFM) and a polarized optical microscope capable of microellipsometry for grain contrast and Kerr microscopy for domain contrast. It was revealed that, for high-asymmetry MIG heads, relatively large leakage of magnetic flux associated with complex multiple domains exists at remanence in the leading-side ferrite surface adjacent to the gap. The strengths of the magnetic flux and the magnetic domain states change irreproducibly when coil current is repeatedly applied. Such a remanent flux associated with the complex remanent state of magnetization distribution in the ferrite can cause an inhomogeneous flux coupling between the head and the recorded track, resulting in readback waveform asymmetry. >

CoPtCr composite thin films were produced by cosputtering nonmagnetic compounds such as SiO/sub 2/, SiN, ZrO/sub 2/, and SiC. These films were prepared without using any underlayer. It was found that the magnetic properties of CoPtCr alloys, such as the in-plane coercivity H/sub c/ and coercivity squareness S*, were significantly improved by admixing nonmagnetic compounds. CoPtCr+SiO/sub 2/ (10 vol.%) composite films were obtained showing a high coercivity of more than 2 kOe for a thickness of 25 nm, without using an underlayer. Torque magnetometer and X-ray pole figure measurements revealed that, when SiO/sub 2/ is admixed, the c-axis of CoPtCr films tends to decline toward the in-plane direction, as a result of the increase of the in-plane anisotropy. From the experimental results of magnetic recording, it was found that the media noise of CoPtCr films was reduced by admixing SiO/sub 2/. >

The addition of light rare‐earth (RE) metal elements (La, Pr, and Nd) to Al thin films with about 2–7 at. % markedly decreases the grain size of the Al matrix more than 50% compared with those of pure Al. Such addition largely suppresses growth of thermal defects of hillocks and whiskers at high temperatures (350–450 °C). A large number of fine metallic compounds of Al11RE3 and/or Al3RE (RE=La, Pr, and Nd) were segregated in an Al matrix, mostly at grain boundaries, after annealing at 350 °C. The resistivities of the films after annealing at the above temperatures show low values of less than 6 μΩ cm compared with those of current thin‐film‐transistor liquid‐crystal displays gate electrode materials (more than about 15 μΩ cm), without the salient formation of hillocks or whiskers on the surfaces.

Ferrite MiG heads intended for narrow track (≲10 μm) digital recording were recently investigated in the critical pole‐tip region at the air‐bearing‐surface using micro‐ellipsometry, Kerr microscopy, and electron back‐scatter diffraction from individual grains,1 and using magnetic force microscopy to detect air‐gap remanent fields.2 Comparison of these direct observations with readback‐after‐write waveforms from written test tracks, and consideration of granularity influences on bulk permeability and domain size, indicate that waveform instability and asymmetry from polycrystalline ferrite (PCF) heads would be diminished by suitable size and orientation of the grains.1 The use of single‐crystal ferrite3 (SCF) for advanced laser enhanced etch definition3 of narrow pole MiGs can avoid this type of distortion. However, secondary signals4 often appear as weak pulses separated in time from the main gap pulse. We have associated this effect with a zig‐zag shaped wall seen nucleated and propagated from the pole ...

Magneto-optical recording materials with high remanent Kerr rotation at short wavelengths were successfully obtained in a trilayer form. A NdFeCo amorphous film with in-plane magnetization, but with a large saturation Kerr rotation angle at short wavelengths, was sandwiched between TbFeCo amorphous films with strong perpendicular anisotropy and high coercivity. The trilayer film, Tb20Fe74Co6 (10 nm)/Nd16Fe57Co27 (7.5 nm)/Tb20Fe74Co6 (100 nm), shows a remanent Kerr rotation angle θKr = 0.32° at a wavelength of 400 nm, coercivity Hc = 2.4kOe, and a good square loop (θKr/θKs ∼ 1).

The atomic structure of sputtered amorphous Tb-Fe1-xCoxthin film systems was studied by X-ray scattering. The composition fractionxwas varied systematically, and the basic atomic structures of Tb-Fe1-xCoxfilms were similar as a whole. The interatomic distances in Tb-Fe1-xCoxfilms annealed at 200°C, overall, tend to decrease when the Co content is increased. These distances seem to change discontinuously at a composition of aroundx=0.5. The coordination numbers of the corresponding atoms did not show much correlation with Co concentration except in the case of transition metal atoms around a transition metal atom. In this case, the coordination number increases after annealing, but this increment tends to decrease as the Co concentration increases in Tb-Fe1-xCoxfilms.

Magneto-optical recording materials with high remanent Kerr rotation at short wavelengths were successfully obtained in a trilayer form by sandwiching NdCo amorphous films with an in-plane magnetization between TbFeCo amorphous films with strong perpendicular anisotropy and high coercivity. The effect of the NdCo thickness on the magnetic and magneto-optical properties of the trilayer medium was investigated systematically. The distribution of the magnetization direction in a trilayer NdCo amorphous alloy film was calculated to manifest the reorientation of the magnetization inside the NdCo layer through magnetic exchange coupling.

The feasibility of direct overwrite utilizing a demagnetization field was successfully demonstrated by employing transition‐metal‐rich side Tb‐Fe‐Co‐Cr amorphous films, which is different from previously reported rare‐earth‐rich side films.1,2 For this purpose, 3.5‐in. magneto‐optical discs were made in the form SiN/TbFeCoCr/SiN on a pregrooved polycarbonate substrate. To evaluate the capability of direct overwrite, we chose the writing and erasure conditions in such a way that erasure laser power (PE) was set higher than the writing power (PW), applying a constant weak external field (Hex) directed in the direction of erasure. Thermomagnetic writing and erasure at 1.76 MHz were carried out on a disk rotating at 1800 rpm. The carrier‐to‐noise ratio, C/N, thus obtained was 26 dB in the conditions of PW=8 mW and Hex=−100 Oe. This signal was completely erased by the dc erase procedure (PE=10 mW and Hex=−100 Oe). Furthermore, this signal value was repeatedly obtained by the above writing and erasure sequence....

Fe-Ni-base metallic glass ribbons were rolled “directly” and “indirectly” by changing the rolling direction with respect to the ribbon axis. In the case of direct rolling, no visible deformation bands appeared on the rolling surfaces (except at the edges) but wavy deformation markings appeared on the side surfaces. In the case of indirect rolling, however, the deformation markings developed on the entire surface; they were wavy and straight in appearance on the rolling and side surfaces, respectively. Tensile tests, performed on the samples rolled directly and indirectly show little and much change in fracture stresses, respectively. As a result of the intersecting of plastic flow systems, fracture shear stresses increase by 7% compared with those of as-quenched samples. Fracture shear stresses on a predeformed area were, however, found to be 3% lower than those for an undeformed area. These results are discussed in terms of both work-hardening and work-softening in metallic glasses.

The structure of an Fe83B17 amorphous alloy was examined in detail, mainly by means of small-angle X-ray scattering (SAXS) measurements. The electron density-density correlation derived from the observed intensity had the following characteristic features: a strong correlation concentrated in the short radial distances within about 1.2 nm and a rather weak correlation towards larger distances. After quantitative analysis, it was concluded that a compositional fluctuation occurs on a fine scale of about 1 nm in the amorphous Fe-B alloys, even though phase separation is not present as completely as in the structure model proposed by Boudreaux. Electrical resistivity measurements as well as transmission electron microscope (TEM) observations were performed to investigate the crystallization process. By using the theoretical equation of electrical resistivity reported by Landauer, the temperature dependence for the partially aged amorphous alloys was analysed. The volume fraction of crystalline phase estimated from the present analysis was in good agreement with the results obtained from TEM observation.