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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.

Several metallization schemes using refractory metals have been demonstrated to produce ohmic contacts to diamond via a solid-state reaction process. This process utilizes existing microelectronic techniques and provides strongly adherent contacts which exhibit low contact resistance. Measurements of the long-term reliability of Mo/Au contacts formed by this process on a type IIb diamond crystal are presented here for the temperature range 450 to 625 deg C. The measurements consist of the resistance between two contacts as a function of isothermal annealing time over time intervals in excess of 130 h in a purified inert ambient. The Mo/Au contacts appeared to be stable and reliable at these high temperatures with no indications of deterioration or degradation of performance.

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.

To address the shortfall in adequate M&S software that can model a wide range of electromagnetic problems, PEO-DD(X)/PMS 500 commissioned the development of a plan for delivery of a Validated, Integrated, Physics-based Electromagnetic Radiation (VIPER) tool set. Microwave Office was identified as one of the most promising microwave electronics simulation codes and was selected for further development and verification and validation. This report shows a wide range of EM test cases in which Microwave Office simulations included linear passive components, linear active components, nonlinear components, and system-level circuits.

To address the shortfall in M&S software capabilities for modeling radomes of various types, PEO-DD(X)/PMS-500 commissioned the development of a plan to satisfy these needs. FSS M&S was identified as one of the most promising FSS simulation approaches, and was selected for further development. This report presents a summary of the verification and validation of the enhanced FSS M&S code over a wide range of electromagnetic test cases, including infinite and finite structures. The verification and validation of FSS M&S conducted under this study was extensive, and can be considered a significant success. Of the 16 cases investigated, 9 cases have numerical and measured results for comparison. Each test case considered in this V&V effort was selected to verify the performance of FSS M&S for a specific application or to validate the underlying theoretical framework of the M&S package. No example studied produced less than favorable results. Throughout this study, FSS M&S demonstrated that it can accurately predict the performance of a wide range of radome structures. Based on the reported results, FSS M&S has been verified and validated as a capable FSS radome modeling and simulation tool for use within the DD(X) program.

Natural type IIa diamonds were implanted with boron at 77 K, using a multiple step, low temperature boron ion implantation procedure to produce an approximately uniformly doped p-type layer of about 200 nm thickness. This layer was used to fabricate metal insulator semiconductor field effect transistor devices operating in the depletion mode, with good uniformity from device to device. Two of the devices were used to fabricate a simple demonstration circuit with a voltage gain of two.

An overview of enabling materials technologies required for fabrication of electronic devices on diamond is presented. Emphasis is placed on electronic doping of diamond by boron ion implantation. Van der Pauw resistivity and Hall Effect measurements were used to determine the net carrier concentration, carrier mobility and resistivity of natural and synthetic diamonds implanted under various conditions. The measured results for a range of implantation conditions and post-annealing temperatures are discussed in the context cf a model developed by J.F. Prins1. The requirements placed on ohmic contacts to diamond, and a process for fabricating ohmic contacts, is discussed briefly. Finally, current-voltage characteristics of a simple MISFET fabricated on ion implanted natural diamond are presented and analyzed. 1J.F. Prins, Physical Review B, 38 (1988) 5576.

The recognized need for devices that can perform under severe operating conditions and recent advances in the growth of diamond films at moderate temperatures and low pressures has generated great interest in the exploitation of the many unique properties of diamond for solid state devices. Among these properties are high strength, high thermal conductivity, high band gap energy, high carrier mobility, and high resistance to degradation by exposure to radiation, heat, and corrosives[1,2].

We present evidence in this study that the moving species of metal-semiconductor (metal-Si and metal-Ge) systems under ion mixing conditions are affected by the implantation damage distribution in the sample in accordance with the inverse Kirkendall effect. 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 metal and the semiconductor can contribute to the atomic transport in ion mixing.

The formation of amorphous TiAu alloys is investigated using pulsed ion beam annealing (PIBA). The samples consist of thin multilayers of Ti and Au. It is found that samples with compositions in a two-phase region of the TiAu phase diagram can be rendered amorphous whereas those with compositions corresponding to congruently melting compounds can not. The results suggest that metallic glass formation induced by pulsed ion beam annealing involves melt-quenching. A comparison between ion mixing proccsses and pulsed ion beam annealing is also made. Nous avons etudie la formation d'alliages amorphes TiAu recuits par faisceau ionique pulse. Les echantillons sont composes de films minces multicouches de Ti et Au. Nous avons observie que les films dont la composition entre dans une region biphasee du diagramme de phases peuvent denir amorphes alors que ceux dont la composition coincide avec un point de liquefaction con-gruente restent cristallins. Ces resultats suggerent que la formation de verres metalliques par faisceau ionique pulse impliqne une hypertrempe. Finalement, une comparaison est faite entre les procedes de mixage ionique et de recuit par faisceau d'ions pulse.

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.

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.