摘要:

Experimental results are presented showing the effects of nitrogen implantation on a series of materials that are related to the WC–Co cemented carbides: pure Co, W, Co–W alloys (10–30 wt. % W), and WC (single crystal and binderless). Implantations were carried out at 180 keV, with a fluence of 2.5×1017N+2/cm2at implant temperatures of approximately 400 °C. Results show that nitrogen is not readily retained by pure Co. However, for the Co–W alloys the retained nitrogen increases with the W concentration but the nitrogen profiles are non‐Gaussian and indicate diffusion of the implanted nitrogen. For the W and the WC samples, most of the implanted nitrogen is retained and the profiles have a Gaussian‐type shape similar to those obtained for nitrogen implanted WC–Co cemented carbides. There is evidence to indicate the formation of nitride bonding in the nitrogen‐implanted W and WC samples. Preliminary low‐load (10–25 g) indentation measurements, did not show any significant changes in hardness as a result of nitrogen implantation.

ISSN:0734-2101    

DOI:10.1116/1.574095

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

Composite thin films, having compositions Ni25Cr75and Ni75Cr25, deposited on single crystal silicon substrates were irradiated with a pulsed ion beam. These systems were compared to the binary Ni/Si and Cr/Si systems, and were characterized using Rutherford backscattering spectroscopy, Auger electron spectroscopy, x‐ray diffraction, and transmission electron microscopy. Interfacial melting was observed in all samples. For the Cr/Si and alloy/Si samples, melting occurred at noneutectic interfacial compositions. The phase CrSi2, in a layered structure of nickel silicides (Ni2Si/NiSi/NiSi2), was present in the reacted layers. Auger electron spectroscopy showed that an enrichment of Ni (in the form of NiSi2) occurred at the silicon interface for both alloy compositions.

ISSN:0734-2101    

DOI:10.1116/1.574096

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

CuInSe2thin films were deposited onto glass and liquid‐indium‐coated glass substrates by coevaporation of copper, indium, and selenium. The morphology, composition, and crystalline properties have been studied in relation to the deposition process parameters. The deposition rate and the grain size are higher in films grown on liquid indium than on glass and depend on the indium film thickness. Films grown on indium do not show the same crystalline phases of films grown on glass, and in order to obtain films free of spurious phases the Cu fluxes must be increased.

ISSN:0734-2101    

DOI:10.1116/1.574097

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

The surface oxide chemistry of Hg0.8Cd0.2Te in aqueous solutions with thepH ranging from 1–11 has been determined from the electrophoresis zeta potential. A four parameter acid dissociation model was developed to fit the experimental data. The dissociation of tellurous acid, which was formed by a surface oxide of TeO2combining with water, was found to dominate the surface oxide chemistry forpH between 1 and 9. The point of zero zeta potential (PZZP) occurred atpH = 1.8. The tellurous acid dissociated in a two‐step pattern with surface charge densities of approximately −2×1012electrons/cm2frompH of 4 to 6.5 and −4×1012electrons/cm2frompH of 9 to 9.5. As thepH was increased beyond 10, oxidized Cd dominated the surface oxide chemistry.

ISSN:0734-2101    

DOI:10.1116/1.574098

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

Topographical changes in the surfaces of GaAs (100) crystal by Ar+beam sputtering at various temperatures are studied. It is found that the bombarded surface remains almost featureless in contrast to similar sputtering of metal targets where conical protrusions always appear. However, cones do appear at high temperature with simultaneous seeding with Cu. The results are discussed with a view of Wehner’s recent investigations in the development of conical structures.

ISSN:0734-2101    

DOI:10.1116/1.574099

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

A smooth method of improving the surface texture of thin CdS films is presented in this work. The use of ammonia solution in this matter has been found to be safe, since no deleterious compound is released. The low rate of the process involved allows for an easy follow up of the photoreactive behavior of each of the samples treated for different immersion times. Monitoring of the change that occurred revealed that optimal conditions can be attained from either a single wet treatment of the sample or a repetitive wet treatment of the same sample in the same medium. Microstructure modification is likely to be the main factor responsible for the improvement in photoreactivity. A shiny electrochemical deposit engendered by the second method does not modify this behavior. That compound probably leads to a progressive change of the semiconductor‐electrolyte junction in semiconductor insulator‐electrolyte type.

ISSN:0734-2101    

DOI:10.1116/1.574100

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

A sputtering system which is capable of depositing films onto the disk substrate, rotating at very high speed in the vacuum chamber, has been developed. The maximum rotational speed of about 10 000 rpm has been attained in the Facing Targets Sputtering apparatus for preparing Co–Cr perpendicular recording disks. Properties of the film deposited on the rotating disk substrates have been investigated with regard to (1) the absolute linear velocity (m/s) of the substrates, and (2) the relation between the rotational speed (rpm) of the substrates and the deposition rate of the film. The experimental results show that the linear velocity realized in this study was not high enough to give the significant effects on intrinsic properties of the films. This means that even such a dynamic motion of the substrate does not bring any negative effects on the microstructure of the film. Meanwhile, it has been found that the effect of the substrate rotation appeared very clearly on the growth mechanism of the film. That is, the dispersion of thec‐axis orientation in the Co–Cr film becomes better with the increase of the rotational speed (rpm) of the substrates probably due to the quasiepitaxial growth of the film.

ISSN:0734-2101    

DOI:10.1116/1.574102

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

Specular, crack‐free thin films of the refractory conductor zirconium boride have been deposited for possible applications in combined contact/diffusion barrier metallization schemes. Films were deposited by dc triode sputtering, which allowed the independent study of the effects of sputtering pressure, target voltage, and current on the film properties. The mole ratio of boron in the films increased (composition tending to ZrB2) and the resistivity decreased with increasing deposition rates which at a fixed target voltage and sputtering pressure increased almost linearly with target current. Decrease in sputtering pressure, with only a minor change in deposition rate, dramatically decreased resistivity and caused stress in the films to change from tensile to compressive. X‐ray photoelectron spectroscopy correlated reduced oxygen content to reduced resistivity. Triode sputtering permitted deposition of films at 2 mTorr with a resistivity of 162 μΩ cm which is the lowest reported value for as‐deposited films.

ISSN:0734-2101    

DOI:10.1116/1.574103

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

An experimentally verified useful new model for reactive sputtering is presented. By considering the total system (target erosion, gas injection, chamber wall deposition, reactive gas gettering at all surfaces, etc.) during deposition it is possible to evaluate quite simple relationships between processing parameters. We have expanded earlier treatments to include these phenomena. The model involves that gettering of the reactive gas takes place at the target and at the walls opposite to the target. Arguments are also presented for how the sputtered materials (elemental target atoms and the formed compound) contribute to the formation of the surface composition of the walls opposite to the sputtering electrode. The mass flow of the reactive gas has been chosen as the independent parameter in this presentation. Results for partial pressure and sputter rate are presented. The theoretical values are compared with experimental results from reactive sputtering of TiN. It is also pointed out that the calculated values agree extremely well with results presented in the literature by several other authors.

ISSN:0734-2101    

DOI:10.1116/1.574104

出版商:American Vacuum Society    

年代:1987

数据来源: AIP

摘要:

The sputtering process in Fe–12.5 at. % Si alloy target (cbSi=12.5) of rf planar magnetron system was studied through the target surface and film concentrations by electron probe microanalyzer (EPMA) sampling depth. Si concentration of filmcfSiwas unchanged through total sputtering timetsp=2680 min whilecsSi(target surface) was constant untiltsp≂500 min and decreased with further sputtering. Attsp<500 min concentrations werecsSi=11.6 at. % Si andcfSi=10.7 at. % Si. The deposition rate was initially constant at 720 Å/min while attsp≳1000 min it decreased to 610 Å/min. The anomalous behaviors incsSiwere discussed and metallurgical phase change at target surface was considered but not decisive. The steady‐statecfSi=cbSiwas not observed even at high current density and the sputtering behaviors were interpreted as that the enhanced diffusivity could stretch the sputtering time to reach steady state.

ISSN:0734-2101    

DOI:10.1116/1.574105

出版商:American Vacuum Society    

年代:1987

数据来源: AIP