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The electrochemical reduction of thionyl chloride in 0.5, 1.0, and 1. 5 molar LiAlCl4-SOCl2 solutions was studied at glassy carbon microelectrodes using the technique of cyclic voltammetry. It is shown that the reduction of thionyl chloride in these solutions occurs irreversibly and leads to the deposition of sparingly soluble lithium chloride on the electrode surface. The peak heights for the reduction of thionyl chloride increased linearly with the square root of voltage scan rate and at a fixed scan rate, the peak heights were found to be independent of the electrolyte concentration.

Hall effect and conductivity measurements made on semi-insulating bulk GaAs are examined by a new approach to mixed conduction analysis. Based on Fermi level and electron mobility analyses of conductivity and Hall coefficient, it uses revised values of effective densities of states at the band edges, and electron/hole mobility ratios recently adopted by other workers. The treatment provides a visual analysis of the system in terms of the electrical parameters and impurity densities, and establishes criteria for the onset of mixed conduction. (Author)

Experiments aimed at finding a chemical polish for the doubly rotated SC-cut have been performed with a variety of etchants. The surface morphologies of etched SC-cut plates depend strongly on the composition of the etching solutions. Some of the solutions evaluated did not produce chemical polishing on either side of the SC-cut plates, some produced chemical polishing on one side but not the other, and some were able to polish both sides. It has also been shown that at least up to 10 MHz, the chemical polishing does not produce a significant 0 degradation for AT-cut quartz crystal resonators., Presented at the Annual Symposium on Frequency Control (33rd), 30 May-1 Jun 79, Atlantic City, NJ.

The use of cupric chloride as a cathode additive in lithium-thionyl chloride cells was investigated. Carbon black paste microelectrodes containing 21.7 weight percent of cupric chloride were used to study the effect of cupric chloride additive on cyclic voltammograms, polarization curves and cathode potential during discharge. It was found that the incorporation of cupric chloride in the carbon black cathode structure resulted in lowering of the cathode polarization so that carbon black cathode containing the additive showed higher cathode voltages than the carbon black cathodes without the additive. Cyclic voltammetry at these microelectrodes also showed that the thionyl chloride reduction peak was also shifted to more positive potentials in the cyclic voltammograms. (Author)

Hermetically sealed lithium-vanadium oxide cells were evaluated after one year of storage. From cell capacity measurements, excellent charge retention was found. The energy to weight and volume ratios did not change substantially during storage. The rate capability observed is within practical limits. At 0 degrees C the rate is 31 percent of that at room temperature. (Author)

The design advantages resulting from the linear demagnetization curves of rare-earth permanent magnets are discussed. The magnetic analogue to Ohm's law is derived and its affiliation illustrated by an example. Other aspects of design, such as the replacement of magnetic circuits with equivalent pole densities and the significance of the energy product, are also discussed. (Author)

The anisotropy fields (HA) and saturation magnetizations (4 pi Ms) of the systems Sm2(Co1-xFex)17 and Sm2Mn(Co1-xFex)16 were measured at 4.2 K and 300 K in applied fields up to 100 kOe. The presence of the Mn in the latter system raised the anisotropy fields by as much as 55% over those measured for the corresponding compounds in the ternary system. The augmentation of anisotropy was accompanied by a slight decline in 4 pi Ms of approximately 5% for the materials of highest HA. The values of 4 pi Ms for the quaternary compounds showed much less temperature dependence, increasing by about 5% in going from 300 K to 4.2 K as compared to 15% for the ternary system. A comparison of the present HA results with previous anisotropy measurements of Perkins and Straessler, obtained by extrapolation from applied fields up to 20 kOe showed the latter to be too low by as much as 50%. The effect of the higher HA values on the anisotropy constant Kl and the crystal field parameter r ang 2 will be presented and the consequences discussed. (Author)

This paper describes the processing techniques and characteristics of a graphic documentation software package which was developed for plotting hierarchically-modular circuit design layouts using a dot-matrix printer/plotter. This software can be used for other graphic applications as well so long as the data is supplied in the required descriptive language format. This software package will process modularly partitioned circuits or structures to any nested level and allow accumulative rotation and mirroring (B orientations) of the modules regardless of nesting level. The software uses design data in RCA's Design File Language and accesses data for the modules from library files using searches on name. If the graphic presentations require more than one page width, multiple segments (pages) are spooled out to the printer/plotter with fiducial reference marks for joining the segments together. Complete integrated circuit layouts may be plotted using either cell outlines or complete cell details. Other options include scaling, rotation, windowing, and shading of polygons. A single mask level may be selected for plotting, if desired. (Author)

Alpha aluminum phosphate (berlinite) has been investigated as a highly piezoelectric material potentially suitable for use in advanced bulk and surface acoustic wave devices. Areas of investigation include: (1) crystal structure, (2) methods of crystal growth, (3) defects in structure, (4) the presence of water impurities, (5) piezoelectric resonators, and (6) the equivalent electrical circuit. Calculations have been carried out for frequency constant, piezoelectric coupling factor, and linear temperature coefficient as functions of orientation for general, doubly rotated plate orientations, and disclose quartz-like properties with coupling factors appreciably larger than quartz. Measurements indicate larger than expected losses, indicative of incorporation of impurities during growth; suggestions for further work are given. (Author)

Theoretical considerations predict increased stability of cyclic ethers and diethers against reductive cleavage by lithium if the ethers have 2 methyl substitution. Diethers are solvents with low viscosity which are desirable for high rate rechargeable lithium batteries. Synergistic, mixed solvent effects increase electrolyte conductance and rate capability of lithium intercalating cathodes. (Author)

A series of solutions were investigated for chemically polishing SC-cut quartz crystals. Solutions of concentrations were prepared. It was determined that some of these solutions can chemically polish SC-cut crystals in less time than solutions previously reported. Shorter etching time minimizes the problem of water evaporation from the etching bath. Also, the new solutions are easier to prepare than those employing NH subscript 4 F. (Author)

Papers presented at the sessions addressed the following topics: Electrical applications; medical applications; magnetic bearings and other mechanical devices; magnetic properties; magnetic aftereffect; structures and coercivity; permanent magnets; and resources & refining of rare earth elements.

The physical and electrical properties of GaAs show it to be an important semiconductor material for use in various electronic devices associated with advanced military systems. However, the realization of enhanced device performance has been delayed, partly due to the lack of consistent, high quality, semi-insulating GaAs substrate material. A modified liquid-encapsulated Czochralski technique employing pressure-assisted, in-situ compounding is described. This process, first demonstrated in the United States by the US Army Electronics Technology and Devices Laboratory, consistently yields high resistivity (to 10 to the 9th power ohm-cm) GaAs without the intentional addition of charge compensators. This approach is now becoming the basis for U.S. volume production of large diameter, high quality, semi-insulating GaAs material. An automated system for the measurement of transport properties by use of the van der Pauw method is described. A mixed conduction analysis allows the direct determination of individual carrier concentrations and mobilities, intrinsic carrier concentration and Fermi level. Applied to ET&DL's non-Cr-doped GaAs, this analysis yields electron mobilities higher than Cr-doped material and Fermi levels which are nearly intrinsic. (Author)

High quality annealing of boron implanted silicon 10 to the 15th power/sq cm, 50 keV) was achieved using commercially available quartz xenon flash tubes after a 20 second preheat. Electrically active dopant profiles, obtained from spreading resistance profiles, indicate that the annealing proceeded by solid phase epitaxy. We also find that the degree of boron redistribution can be controlled by the cumulative exposure to the flash. Characteristics of the apparatus used suggest that annealing 3 inch diameter wafers with a throughput of 3 wafers per minute is feasible. (Author)

A study is presented for a high power microwave/millimeter wave amplifier (herein called CEBA) that requires no radio frequency (RF) circuit structure. The electron beam is treated as an active dielectric serving the dual purpose of slow-wave circuit and amplification source. Amplification is obtained when beam-wave synchronism is met. The RF wave, generated by an antenna, propagates inside an oversized waveguide and interacts with a solid or hollow electron beam that guides the RF energy. Two theories are presented for achieving an electron beam with isotropic permittivity and permeability characteristics. The electron beam and magnetic field parameters for obtaining this isotropic condition are given and the importance of the cycltron frequency and Doppler effect are described for achieving low voltage and low magnetic field operation. The RF field that can propagate on the electron beam is characterized by the electric field equal to the magnetic field multiplied by the intrinsic impedance and the imaginary j phase factor. The boundary value problem is solved with emphasis on solutions for the lowest order mode. Computer generated design data show the propagation constant and growth factor as functions of frequency for selected values of plasma and cyclotron frequencies; bandwidth characteristics; and beam parameters.

A simplified method is presented for the analysis of conductivity data for complex situations which involve ion pairing. The method was tested by comparing results with more elaborate analyses using published data for a number of salts in various solvents. The method is then used to analyze the conductivity data for several salts in thionyl chloride. These latter analyses are important for selecting electrolytes for lithium primary batteries. (Author)

Conductivity and Hall measurements were made on semi-insulating GaAs samples grown with a recently developed process using in-situ compounding with liquid encapsulated (B2O3) Czochralski growth techniques. Mixed conduction analysis in combination with a nomographic analysis of charge balance and conduction was used to elucidate compensation in this material. Given the Cr concentration in one sample, the use of an iterative self-consistent procedure allowed the deduction of total donor and acceptor concentrations for identically prepared Cr-doped and undoped samples. Further analysis yielded the compensation ratio and energy level of the dominant acceptor of a third specimen. A subsequent spark source analysis confirmed the high purity of this in-situ compounded material, as well as the conclusions and utility of the nomographic analysis. (Author)

The dissolution of selected electron-beam resist polymers was studied by wide-line-NMR/Dynamic Nuclear Polarization signal enhancement techniques under experimentally restrictive conditions. It was demonstrated that d(6) -acetone is suitable for NMR-based dissolution studies, and that the amount of polymer required for a dissolution experiment can be reduced by a factor of ten (to 0.2 g) by selection of novel radical spin polarization materials. Studies of scarce experimental or irradiated polymers are now more feasible. The beneficial effects of carboxylate- and halocarbon substituents on the dissolution properties of methacrylate resists were demonstrated. An attempt was made to investigate the effect of various parameters on dissolution properties in acetone slurry (irradiation, molecular weight, molecular weight distribution, polymer surface characteristics or morphology), but in the unstirred environment of the experimental set-up, dissolution properties consistently ran counter to those expected from dissolution theory for well-mixed systems. The existence of a gel barrier to dissolution was not only inferred from the dissolution experiments, but also could be confirmed visually in selected samples. The gel barrier phenomenon may affect dissolution behavior inside the freshly-cut channels of the resist, where convection would be least effective. In other dissolution experiments, it was demonstrated that the sensitivity of the instrumentation is not sufficient to make 19-F NMR an acceptable alternative to 1-HNMR in dissolution studies of fluoropolymers. (Author)

The required miniaturization of military IC devices to submicron and ultra-submicron dimensions in the 1980s raises serious questions regarding the use of electron beam (e-beam) lithographys an appropriate fabrication technique for this end. In this paper it is shown that the ultimate resolution of the e-beam process is determined by electron scattering effects in the lithographic resist material and by electron back-scattering from the underlying device substrate. The merit of the e-beam fabrication technique for use in very high speed integrated circuit (VHSIC) technology is assessed. A study is presented which describes the electron scattering and backscattering processes in electronic materials. A theoretical analysis describing primary electron backscattering from single- and double-layered substrates is presented; also, attention is focused on the question of the spatial region exposed by a scattered e-beam in a lithographic e-beam resist material. Experimental electron backscattering, e-beam, and scanning electron microscopy studies are used to corroborate theoretical findings. (Author)

Polarization and discharge curves were measured for sulfuryl chloride reduction at Teflon-bonded carbon cathodes fabricated using a number of different carbon powders. Lithium chloroaluminate was utilized as electrolyte solute. At moderate current densities, cathode polarization tends to normalize with respect to Brunauer, Emmett, Teller (B.E.T.) surface area of the carbon. Cathode life increases with increased porosity of the electrode. The porosity is required for good accommodation of product LiCl. A formulation incorporating both high B.E.T. area and porosity was developed and found to provide good electrochemical performance against lithium counter-electrodes. When sulfuryl chloride is reduced at the optimized cathode (against a lithium anode), the main products of reaction are LiCl (which is quantitatively) deposited within the electrode's pores) and SO2. This suggests the overall cell reaction: 2 Li+SO2Cl2 yields 2 LiCl+SO2. The addition of Cl2 or SO2 to the electrolyte causes decrease or increase of cathode polarization, respectively. This may be taken as evidence that the reduction, at moderate current densities, occurs through a Cl2 intermediate resulting from heterogeneous decomposition of SO2Cl2. Reduction of undissociated SO2Cl2 may occur at high current densities or after the active area of the electrode is significantly reduced through deposition of product LiCl.

The scanning photovoltage technique was used to image the semiconductor-oxide interface region of MOS capacitors based on silicon and on GaAs. The technique gives a 'photovoltage image' of optically active defects at the interface. Various types of defects and gross imperfections were observed. In the case of the GaAs MOS capacitors, a high density of gross imperfections resulting from surface damage was observed on lightly etched samples. Heavier etching was noted to eliminate this damage and the lower defect density can be correlated with improved device performance. (Author)

This report describes the design and resulting performance of an N-way in-phase power divider/combiner that was first devised and described by U. Gysel. Since closed form solutions for the transmission line elements do not exist, computer aided design and optimization were used to generate design tables for 2- to 8-way divider/combiners with up to 50 percent bandwidths. The design tables along with a CAD program listing are presented. (Author)

The electrochemical and chemical behavior of copper and copper chlorides was studied in 1.5 molar LiAlCl4-SOCl2 solutions using cyclic voltammetric, controlled potential electrolysis and x-ray techniques. It was shown that copper metal reacts with thionyl chloride even at ambient temperatures resulting in the formation of cuprous chloride and cupric sulfide. In LiAlCl4-SOCl2 solutions, cuprous chloride is further oxidized, chemically as well as electrochemically, to cupric chloride. Cupric chloride was found to be electroactive in these solutions and undergoes reduction in the solid state to cuprous chloride and copper, respectively. It was also found that due to the presence of copper chloride films at the copper metal electrode in these solutions, the electrochemical reduction of thionyl chloride at copper electrodes occurs at more negative potentials than observed at carbon electrodes. (Author)

The acceleration sensitivity of SC-cut crystal resonators is an important consideration with regard to modern communications, navigation and identification systems. This report describes a simple method for the location of the mounting positions for a three-point support configuration. Crystallographic directions are related to piezoelectric measurements and polar etching results. A conoscopic method is then used to locate the support positions. (Author)

This report discusses materials and techniques now being used for the fabrication and assembly of hybrid microcircuits. Hybrid technology provides the means for assembling all major categories of electronics in relatively small enclosures to fulfill size requirements which cannot be met by more conventional packaging techniques. Analog and digital circuits as well as microwave modules are made in hybrid form. The design, fabrication and testing of hybrid microcircuits are included along with the present status of thin and thick film components and assembly techniques. (Author)

The Electron Beam Semiconductor (EBS) concept has existed for three decades; but only within the last decade has an active, well-defined program been underway to develop devices that can operate as high-power radio frequency(RF) amplifiers, fast risetime switches, and current and voltage pulse amplifiers. This report discusses the test procedures, data and results of reliability testing of RF and video pulse EBS amplifiers at Electronics Research and Development Command (ERADCOM), Fort Monmouth, New Jersey. Also, the experimental analysis of the series-connected diode EBS device is described in detail. Finally, the report concludes with a discussion of the state-of-the-art of EBS and future trends of the technology. (Author)

The electrochemical reduction and oxidation of sulfuryl chloride in 1 molar LiAlCl4-So2Cl2 solutions were studied at glassy carbon electrodes using the technique of cyclic voltammetry. It was found that the reduction of chlorine, which is formed by the decomposition of sulfuryl chloride, precedes and obscures the reduction of sulfuryl chloride. Thus, in chloride rich solutions, sulfuryl chloride reduction peak in the cyclic voltammograms is completely masked by the chlorine reduction peak. However, in solutions saturated with sulfur dioxide, the chlorine reduction peak is relatively smaller than the sulfuryl chloride reduction peak. The reduction of both chlorine and sulfuryl chloride leads to the deposition of insoluble lithium chloride at the electrode surface and results in its passivation. The electrochemical oxidation of LiAlCl4-SO2Cl2 solutions leads to the formation of chloride, first by the oxidation of AlCl4(-) ions followed by the oxidation of sulfuryl chloride. (Author)

This report covers the design and development of automatic test equipment used to evaluate transistor, microcircuit, and hybrid circuit devices undergoing field tests in the Panama Canal Zone. The devices under test are returned annually to the ERADCOM, Electronics Technology & Devices Lab, Fort Monmouth, for data collection and data processing. The test system is computer-controlled, providing automatic device parameter measurement and data manipulation, which include data editing, data printouts, and device performance summaries. (Author)

A major Army rocket system may incorporate the use of an electronic fuze timer fabricated using two plastic encapsulated hybrid microcircuits and one encapsulated monolithic integrated circuit. The Electronics Technology and Devices Laboratory at Fort Monmouth, New Jersey was tasked with assessing the storage reliability of these devices through accelerated testing and detailed failure analysis to determine failure mechanisms. From this analysis, corrective actions would be proposed which could permit attainment of the desired reliability. (Author)

These papers discuss application of hybrid microcircuits in government communications, surveillance and other military electronics equipment. Military use of hybrid microcircuits, past and future were described along with microwave techniques, and progress in film technology and tape processing. Included are papers on advanced processing and manufacturing, new packaging techniques and manufacturing/quality controls. (Author)

This report describes a MACI program for obtaining a long life X-ray tube for the AN/TAQ-2 system. New design features, based on a previous research and development program, were incorporated into a commercially available X-ray tube. The new features include a large area, heat treated anode, a getter and an extended cathode baffle. The program successfully resulted in an eight-fold improvement in tube lifetime. (Author)

There are urgent requirements for millimeter-wave oscillators in the range of 60 GHz, particularly for local oscillators, receivers, and low power transmit/receive applications such as the self-oscillating mixer. This report describes the design, fabrication and evaluation of a low cost Gunn diode oscillator structure where the diode is placed adjacent to a dielectric waveguide, which in turn, provides output coupling for radiation. Ten milliwatt output power was obtained from a diode at a frequency of 60 GHz. (Author)

The anodic and cathodic behavior of molybdenum trioxide electrodes in various states of lithiation was investigated in 1M LiClO4-PC electrolytes at room temperature. A comparison was made between the anodic and cathodic rate capabilities of the electrodes. From cycling experiments at various depths of discharge, cycle life data were obtained. Problems observed after deep discharges are discussed. (Author)

The development of the current high contrast, sunlight legible, thin- film electroluminescent display technology will be reviewed and device structures and operating characteristics will be described. Drive and addressing considerations will be presented in relation to device types, power dissipation, multiplexing and viewability. An overview of the industry status will be given including device availability and problems remaining to be solved. Applications of the technology will be reviewed covering both user requirements and device capabilities. A survey of future prospects will cover improvements in efficiency, multicolor displays and various device configurations. (Author)

Self-oscillating mixers in both dielectric and waveguide cavities have been investigated in the 60 GHz frequency range. The devices consist of negative resistance diodes of GaAs and InP material coupled to waveguide cavities or high resistivity dielectric cavities such as silicon or Al2O3. Experimental measurements show that these devices have a sensitivity in the order of -80dBm with the intermediate frequency at 60 MHz and an IF bandwidth of 120 MHz. Applications are suggested based on minimum detectable signal and RF power capabilities for systems requiring small size and low cost. (Author)

The acceleration sensitivity of crystal oscillators is assuming increasing significance in modern communications, navigation and identification systems. This report describes how acceleration, particularly vibration, effects the frequency of quartz crystal controlled oscillators. Simple harmonic motion, complex and random vibrations, and frequency multiplication are covered. Several examples and experimental demonstrations are given. (Author)

This report describes resonator configurations that are compensated for arbitrary directions of the acceleration field, and that require no additional electronics other than the oscillator circuitry normally used. This approach produces compensation with no changes in size, weight, and power, and applies to any crystal reference oscillator in any shock/vibration environment. (Author)

The oxidation kinetics of thermally grown silica on silicon are examined. It is concluded that the current kinetic equations do not agree with the proposed defect models for transport through silica. Suggestions for additional experiments are made. (Author)

The design and experimental findings of a novel approach for a relatively simple, low cost, frequency scanning millimeter wave antenna are described. The antenna consists of a silicon dielectric rectangular rod with periodic metallic stripe perturbations on one side. The feasibility of electronically scanning through a range of angles by varying the frequency fed into the silicon rod is shown. Calculations were made to determine the allowable physical size of the silicon rod in order to maintain a single fundamental mode of operation and the effect which size variations and perturbation spacing have on the angle of radiation and the range of angular scan for a given frequency shift. Efforts covered the frequency range 55 GHz to 100 GHz with specific points of interest at 60, 70 and 94 GHz. The results of experiments conducted are compared with the theoretical calculations. (Author)

The effect of using various materials having different relative dielectric constants on the theoretical design of millimeter-wave line scanning antennas has been examined. Three typical dielectrics were chosen for comparative purposes; silicon (epsilon(r) = 12, sapphire (epsilon(r) = 9.4), and boron nitride (Epsilon(r) = 4). Theoretical calculations were made for each material over the frequency range of 60 to 220 GHz, with special emphasis at 94 GHz due to its increasing use in new millimeter-wave systems. Comparisons were made among the dielectric materials in regard to their maximum allowable physical size for single E(y) 11 mode operation. Using each of the three dielectrics with periodic surface perturbations as a line scanning antenna, the effects on the angle of radiating energy due to changes in the waveguide size and perturbation spacing were determined and evaluated.

Samples from 10 vendors of CMOS 4001 plastic encapsulated integrated circuits were tested in an autoclave at 121 C, 100% RH and 15 psig with and without electrical bias. Twenty-nine test groups of 16 circuits each accumulated over 200,000 device hours. Failure analyses were performed to verify moisture related electrochemical aluminum metal corrosion on the die. Weibull failure distributions showed large differences in moisture resistance reliability among the various vendor products. Test devices with newer data coded packages had longer median life times. There was no correlation of median life time between groups with and without electrical bias. (Author)

Doubly rotated cut quartz possesses many desirable features for acoustic wave devices. In addition to its excellent temperature behavior, it nonlinear elasticity produces mechanical and thermal stress-compensating effects. Doubly rotated cuts of quartz have been extensively used to construct bulk wave resonators for frequency-stable sources. In this report we will describe the acoustic properties of Surface Acoustic Waves (SAW) and Shallow Bulk Acoustic Waves (SBAW) on doubly rotated quartz. A number of delay lines have been constructed on various doubly rotated cuts of quartz. The frequency response of SAW is similar to that obtained on ST-cut quartz. The three SBAW modes predicted from theory were also observed. Both theoretical and experimental results are presented. (Author)

Criteria for determining the quality of inner lead bonds were developed from pull test failure studies. Two thickness types of gold plated copper lead-gold bump samples and one type of tin plated copper lead-gold bump sample were evaluated. Bonding conditions and bond quality were related. Pull testing was performed on bonded samples which had been subjected to elevated temperatures. The types of bond and lead failure modes are described. Pull test results include the percentage of each failure type, average pull strengths in grams and kg/sq mm, and standard deviations. The thicker type of gold plated lead-gold bump system was superior in quality to the other two metallurgical systems. No pull test (destructive) failures occurred at the bump-lead interface for the thicker gold plated lead system. An average pull force value of 48 grams was determined for that system. Minimum values obtained in this study were approximately 1 order of magnitude in excess of bond strengths associated with wire bonds. It was determined that 20 grams force would be a reasonable limit value for non-destructive pull testing of inner lead bonds. (Author)