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In the preceding paper, Paper I, we described an analytical technique, based on ion‐induced x‐ray yields, for detecting low‐Z impurities in medium‐Z targets. In this paper, Paper II, we report the application of this method to the lattice location of impurity atoms. Two systems have been examined to test the method, viz., P and S implants in Ge single crystals. The channeling effect was applied to the phosphorus and sulfur K x‐ray yields excited by 0.5‐MeV protons. Some 93% of implanted 31P (0.7 × 1015 atoms cm−2, room‐temperature implant, 450°C anneal), were found to occupy substitutional sites; the fraction dropped to [inverted lazy s] 63% for an implant dose of 2.7 × 1015 atoms cm−2. Channeling effect results in 〈110〉, 〈111〉, and 〈100〉 directions for Ge(S), implanted at room temperature and annealed at 450°C, prescribe a preferred off‐lattice (> 0.3 Å) site for the sulfur, necessarily different from the regular tetrahedral or hexagonal interstitial sites. For hot (220°C) implantation conditions, poorer crystal annealing and weaker channeling effects were observed.

The usefulness of ion‐induced x‐ray yields to detect low‐Z impurity atoms at low concentration in medium‐Z targets and to locate their lattice sites in single crystals is established in this and the paper that follows. In paper I we describe the technique used with specific reference to phosphorus and sulfur implants in germanium crystals. Particular attention was given to the origin of the different components that constitute the backgrounds in the x‐ray energy spectrum. Peak‐to‐background ratios for these two impurity signals were then determined for H and He ions in the energy region from 0.5 to 2.0 MeV. Some results for N and Ar ions were also obtained. A beam of 0.5‐MeV H+ gave optimum conditions for foreign atom location studies.

Recent measurements of radiation from certain rare gas–halogen mixtures have indicated the efficient production of broadband emitters in the visible. This paper reports a gain measurment at 4416 A˚ in mixtures containing the two emitters tentatively identified as Kr2F* (λmax=4000 A˚ and FWHM=900 A˚ and ArXeF* (λmax=4600 A˚ and FWHM=900 A˚). Attenuation of the 4416‐A˚ probe laser during electron‐beam and electron‐beam‐sustained discharge excitation of 2–3 atm pressure mixtures of argon‐krypton‐fluorine and argon‐xenon‐fluorine indicates absorption only. The fluorescence signals from ArXeF* and XeF* (Ar/Xe/F2 mixture), and KrF* and Kr2F* (Ar/Kr/F2 mixtures) were monitored simultaneously with the absorption of the probe laser. Since the absorption was not proportional to the fluorescence of these species, it is tentatively concluded that it is due to another transient species. Typical absorptions of 10−3 cm−1 were observed at pump levels of 105 W cm−3. A knowledge of the absorption mechanism will be required to assess the efficiency with which such lasers can be made to operate, if at all.

Recently, we reported on the development of a new thin‐film organic solar cell with an AM1 sunlight efficiency of about 0.7% for large area devices (∼1 cm2). This relatively high‐efficiency MIS‐Schottky barrier‐type cell was based on merocyanine type photosensitizing dyes. In this paper we present additional experimental results and develop a comprehensive theoretical model to explain the observed photovoltaic properties. The model incorporates the gneraion, transport, and surface dissociation of excitons and field‐dependent quantum efficiency. The low fill factor of 0.3 was attributed mainly to the field dependence of quantum efficiency. An exciton diffusion length of A˚ was determined by analyzing the short‐circuit photocurrent action spectra using the theoretical model developed. The diffusion potentials for metal/merocyanine Schottky barrier cells for six different metals were determined by C‐V measurements; the diffusion potential increases with decreasing work function. As solar cells, these devices have higher efficiencies when there is a very thin interfacial oxide layer between the barrier forming metal and merocynanine.

Discharge development processes, such as homogeneous glow formation, glow‐to‐filamentary arc transition, and arc formation, of moderate volume CO2 TEA laser medium with external ultraviolet (uv) volume preionization are studied by a high‐speed‐camera technique. The framing records in this paper supplement the earlier streak ones of CO2 TEA laser discharges of Sakai etal. The records show that instability appears as a bright spot at the cathode in the middle of the uniform glow stage, then propagates in the anode direction, keeping the shape of a bright spot or changing into a bright filament. This propagation continues even after termination of the volume‐dominated glow. The discharge development is found, from an understanding of the current waveform, to be considerably sensitive to the CO2, N2, and He composition ratio, and the pulse‐forming network and other characteristics are also studied. The glow‐to‐arc transition mechanism and the dominant contributor to suppress arc formation are discussed.

The potential barriers of ultrathin (%40 A˚) SiO2 layers to electrons and holes tunneling between the semiconductor and the metal have been measured independently on the same MOS samples by a new experimental technique introduced in this paper. The method combines dark measurements of current and capacitance versus voltage with measurements of photocurrent suppression under optical illumination. The results show that the tunneling barriers for holes are consistently much larger than those for electrons.

Rare earth intermetallic compounds possess crystal field interactions which can be observed as contributions to the heat capacity. This paper reports the results of heat capacity studies of several RFe2 compounds (R=Ho, Er, and Lu). The crystal field contributions to the heat capacities for the Ho and Er ions, determined from the heat capacity data obtained for HoFe2 and ErFe2, have been used in determining the crystal field parameters for these rare earth ions. In our case, for Er3+, B40=1.937×10−3 K and B60 =−1.195×10−5 K; and for Ho3+, B40=−9.40×10−4 K and B60=5.10×10−6 K. These parameters are discussed and compared to those obtained by neutron diffraction and spin reorientation studies.

The elucidation of the electronic structure of rare earth metal hydrides, particularly lanthanum, has been of interest for many years. This paper reports the preliminary results of electron paramagnetic resonance (EPR) studies of lanthanum hydrides with hydrogen to metal atom ratios (H/M) from 2 to 3. EPR linewidths and line intensities are reported as a function of temperature and hydrogen concentration. Anamolous behavior of these parameters has been observed and is discussed.

In an earlier publication 1 we reported aspects of magnetokinetic studies on the oxidation of FeS2 carried out as a function of its particle size (90 to 250μm) and temperature (400–500 °C); in this study we considered mostly the formation of α and γ Fe2O3. In the present paper we have considered the formation of other oxidation products such as (a) Fe2  (SO4)3, and (b) superparamagnetic particles of α Fe2O3. Mo¨ssbauer spectroscopy has confirmed the presence of (a) and, coupled with X‐ray line broadening studies has shown the absence of (b). The yield of Fe2  (SO4), is found to increase with decreasing starting particle size of FeS2. Using our earlier results 1 we have obtained values of (dM/dt) from the initial slopes of the magnetization (M) vs. time curves for particle sizes (180 to 250 μm). From plots of ln (dM/dt) versus 1/T an activation energy of ∼7 Kcal/mole has been obtained for the following predominant reaction: FeS+(11/4)O2→ (1/2) αFe2O3+2SO2. This value compares favorably with values reported by other workers2 who used classical thermogravimetric analysis.