摘要:

The optical absorption of doped and undoped hydrogenated amorphous silicon (a‐Si:H) films ranging from 5 nm to 10 &mgr;m was measured using photothermal deflection spectroscopy. The absorption spectra show that there is a high defect layer associated with the surface or interface of the film. From comparison of defect absorption and dangling bond spin densities, it is found thata‐Si:H films which have ∼1015bulk defects/cm3exhibit surface or interface layers with ∼1012dangling bonds/cm2.

ISSN:0003-6951    

DOI:10.1063/1.93762

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The diffusion of zinc into GaAs and (GaAl)As was studied using a high resolution microsectioning technique. Diffusions were performed into epitaxially grown thin layers comparable to those used in injection laser structures; several boat grown GaAs were also studied. The diffusions were done at a temperature commonly used in device processing; a three‐phase diffusant was used to preclude sample dissociation and damage. A diffusion coefficient of Zn in GaAs of 1.4×10−11cm2 s−1was obtained, and this is in good agreement with the extrapolation of the values obtained at higher temperatures. A marked difference in the diffusion profiles of GaAs and (GaAl)As was observed.

ISSN:0003-6951    

DOI:10.1063/1.93763

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A dramatic dependence of the resistivity on an external magnetic field gradient has been observed for the first time in ap‐type semiconducting calcium‐doped yttrium iron garnet film. In a homogeneous gradient a steady increase of the conductivity (up to 26%) is detected, while by applying a nonuniform gradient only transient variations are found. These results are interpreted as due to an intrinsic physical process independent on the nature of the sputtered contacts. A hole trapping/detrapping mechanism is suggested to qualitatively explain the results in a uiform field gradient and, in particular, the long relaxation times measured.

ISSN:0003-6951    

DOI:10.1063/1.93764

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The fringing field above the surface of a magnetic recording head or magnetic tape can be studied in transmission in the scanning electron microscope (SEM) by either the ‘‘image distortion’’ or the ‘‘Schlieren’’ method. In the image distortion method, the magnetic field is calculated from the distortion caused by the fringing field to the image of either the specimen itself, or of a reference mesh. The Schlieren image shows a contour of equal field‐times‐distance integral (either for the total field or for a specified component of the field) directly. Methods used previously to show the contours of constant values of this integral in the SEM can be improved by the use of the rocking scanning mode about the plane of the aperture stop. The Schlieren method can also give a two‐part image in which one‐half of the micrograph shows the surface of the head viewed at a glancing angle, while the other half of the image shows the fringing field. This method has the potential for stroboscopic operation.

ISSN:0003-6951    

DOI:10.1063/1.93765

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

We have applied the recently developed technique of fluorescent thermal imaging to measure the surface temperature profile of a test sample with unprecedented temperature and spatial resolution. A particularly simple temperature profile was produced by passing an electrical current through a long, unresolvably thin metal stripe on a glass substrate. The sample was coated with a fluorescent thin film whose fluorescence efficiency decreases with increasing temperature. Digital processing of the fluorescence image produces a quantitative surface temperature map with simultaneous temperature and spatial resolutions of 0.08 °C and 0.7 &mgr;m, respectively. This spatial resolution approaches for the first time the dimensions of state‐of‐the‐art integrated circuits. Extension of this technique into the nanosecond time domain will allow new advances in the fields of photothermal microscopy, integrated circuit diagnostics, and thermal transport measurements.

ISSN:0003-6951    

DOI:10.1063/1.93766

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The secondary emission of electrons from uranium surfaces was studied as a function of energy and type of the bombarding ions in the range 1.0–5.0 keV. The value of the secondary electron yield (i.e., the number of electrons ejected from a surface per impinging ion) was found to increase linearly with increasing ion energy and to scale roughly as the inverse square root of the mass of impinging ions.

ISSN:0003-6951    

DOI:10.1063/1.93744

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The stress in molybdenum films deposited by dc magnetron sputtering in neon has been characterized. Fabrication of 1‐&mgr;‐thick films 2 cm in diameter on polyimide membranes has been achieved with low‐stress material. A reactive ion etching process is described with 75‐nm resolution and 15:1 aspect ratios.

ISSN:0003-6951    

DOI:10.1063/1.93743

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The conventional concept that there is a so‐called Fermi level for electronic states in solution which can be identified with the reversible potential on the vacuum scale of a redox couple present in solution (and in equilibrium with an electrode therein) is not valid. The inner potential of the solution phase should be added to the redox potential (on the vacuum scale) to achieve identity (at equilibrium) with the Fermi level energy of the electron in the metal to that in the solution.

ISSN:0003-6951    

DOI:10.1063/1.93745

出版商:AIP    

年代:1983

数据来源: AIP