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A simplified version of the specific contact resistance measurement scheme of G. K. Reeves [Solid State Electronics 23, 487 (1980)] has been developed. Its applicability to semiconducting diamond is demonstrated using four sample types: epitaxial films doped to mid 1019 acceptors/cm3 on 〈100〉 and 〈110〉 type IIa substrates; type IIb diamonds 0.25 mm thick, and type IIb diamonds thinned to 0.035–0.05 mm thick. The ohmic contacts were based on a solid‐state annealing process using carbide forming metals. The measured specific contact resistance depends mainly on the doping level in the diamond. Measured values ranged from 8×10−6 Ω cm2 for heavily doped films to 1×10−2 Ω cm2 for lightly doped bulk samples. A simple analysis shows that the contacts to highly doped layers are suitable for device applications.

A natural IIa diamond was implanted with boron ions at a substrate temperature of 80 K. Ohmic contacts (Mo/Au) were formed using a solid‐state reaction process. Van der Pauw resistivity/Hall measurements were taken as a function of temperature from room temperature to nearly 600 °C. Heating to approximately 350 °C was necessary to stabilize resistance values to over 3.4 MΩ/sq and 1.3 MΩ/sq for the unimplanted and implanted sides, respectively, indicating possible hydrogen incorporation into the diamond during annealing of the metallized sample in hydrogen. Comparison of the electrical properties of the implanted and unimplanted sides showed that the boron implant introduced electrically active acceptors.

The origin of the motion of semiconductors during ion mixing was investigated by studying both the temperature and the atomic mass dependence of moving species in the GexSi1−x/Ni and the GexSi1−x/Pd systems. Ion mixing was performed with 280‐keV Ar ions at temperatures between 30 K and room temperature. The atomic mass of the GexSi1−x alloy was adjusted by changing the concentration of Ge in the alloy. In thermally induced reactions, no preferential motion of Si or Ge was observed. During ion mixing, the atomic flux of Si was observed to be enhanced compared to that of Ge. The atomic flux of the sum of Si and Ge to metal decreases with increasing substrate temperature during mixing and with increasing Ge concentration in the GexSi1−x alloy. From the strong atomic mass dependence of the moving species during ion mixing it is concluded that the origin of the motion of semiconductors under ion mixing conditions is due to the effects of secondary recoils.

X‐ray photoemission spectroscopy was used to analyze the oxide grown at low temperature on AuxSi1−x films. It was found that the oxide is stoichiometric SiO2, but is structurally distinct from oxides grown on Si at high temperatures (950 °C). Also, unoxidized Au‐Si atom inclusions were observed in the oxide. The composition of the inclusions is dependent on the initial bulk AuxSi1−x composition.

Low dose ion implantation through the Pt/Si silicon interface prior to annealing has been shown to yield a more planar PtSi/Si interface after annealing. The electrical characteristics of these ion mixed diodes have also been shown to be more uniform from device to device as well as more nearly approaching theoretical performance than conventionally prepared diodes.

The relative importance between the thermodynamical driving force and kinetics in thermal annealing and ion mixing in the thermally activated regime has not been clarified. To probe the role of the thermodynamical driving force in reactions between metals and silicon, the Co‐Si system was chosen for investigation. In general, three silicide phases are formed during thermal annealing of samples consisting of Co thin films deposited on Si substrates, i.e., Co2Si (the first phase to form with a heat of formation, ΔHf=−9 kcal/g atoms), CoSi (ΔHf=−12 kcal/g atoms), and CoSi2 (the last phase to form, with ΔHf=−8.2 kcal/g atoms). Previous experiments have shown that annealing a sample of Si/CoSi/Co converts CoSi into Co2Si instead of a continuous growth of CoSi. This type of reaction is apparently unrelated to the magnitude of the thermodynamical driving force since ΔHf of CoSi is significantly larger than those of Co2Si and CoSi2, but is kinetically restricted instead. Under ion mixing conditions the kinetic re...

We present evidence in this study that the moving species under ion mixing conditions are affected by the implantation damage distribution in the sample. This observation holds for metal‐semiconductor, metal‐metal, and semiconductor‐semiconductor systems. The direction of thermal annealing atomic transport appears to play a role in ion mixing as well. When these two factors are in the same direction, only one dominant moving species is observed. When these two factors are in opposite directions, both constituents can contribute to the atomic transport in ion mixing.

In this letter we report the observation of surface segregation of gold from AuxSi1−x alloys with 0.25

The accuracy of lattice parameter determinations by Read camera x‐ray diffraction is shown to be strongly dependent on camera alignment. Alignment of the Read camera eliminates the main sources of error. Further improvement in analysis was achieved by constructing a collimator with a rectangular cross section. Analysis and testing showed that the rectangular collimator enhances the efficiency, resolution, precision, and peak‐to‐background intensity ratio for x‐ray analysis of thin films using the Read camera.

We have investigated the oxidation behavior of co‐deposited Au‐Si films at low temperatures (∼200 °C). Alloys spanning the Au‐Si phase diagram have been examined. Films with greater than 40 at. % Au were found to oxidize forming SiO2, while films with less than 40 at. % Au were found to be relatively stable in an oxidizing ambient. This phenomenon was used to form Au lines with a self‐passivating SiO2 coating. The resistivity of these lines is estimated to be 6–10 μΩ cm.

Optical waveguides fabricated by argon ion mixing in InGaAs/InP superlattice structures grown by low‐pressure metalorganic chemical vapor deposition are demonstrated for the first time. Implantation of argon ions at ∼400 °C eliminates the need for a high‐temperature post‐anneal to induce the compositional disordering. As‐grown and argon‐implanted samples were studied using x‐ray diffraction and optical absorption measurements. Planar buried rib waveguides operating at a 1.5 μm wavelength are fabricated by selective ion implantation.