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The characteristics of human S-100 beta-positive T lymphocytes (S-100 beta+ T cells) and their fluctuation in peripheral blood under normal and various pathologic conditions were investigated. S-100 beta+ T cells were small lymphocytes with no particular subcellular structures and showed a proliferative response to mitogens. They were present mainly in peripheral blood under normal conditions but accumulated in T zones of lymph nodes with nonspe- cific T-zone hyperplasia, where numerous interdigitating reticulum cells existed. In healthy adults approximately 1 % to 4% (mean 3.4%) of peripheral blood mononuclear cells were S-100 beta+ T cells. The proportion of S-100 beta+ T cells in peripheral blood tended to significantly decrease (<0.5%) in patients with neoplastic diseases; this tendency was apparently related to tumor progression.© 1987 by Grune & Stratton, Inc. 0006-4971/87/7001-0032$3.00/0

We have successfully grown epitaxial GaSe films on GaAs(111), (001) and (112) by molecular beam epitaxy. On the GaAs(111) substrate, the c-axis of the GaSe layer was perpendicular to the substrate surface, while each unit layer of GaSe was inclined on GaAs(001) and (112) substrates when the growth temperatures were higher than 500°C at high beam fluxes of Ga and Se. Furthermore, we could detect strong photoluminescence (PL) emission from the GaSe films grown on GaAs(001) and (112) substrates. This result suggests that crystal quality was improved by growth through chemical bonding at a higher growth temperature.

Amorphous Si solar cells with delta-doped (?-doped) p-layers were prepared by a multichamber photochemical vapor deposition (photo-CVD) system. By optimizing the structure of the ?-doped p-layer, a conversion efficiency of 12.3% (AM1) was obtained for small-area solar cells with a ?-doped p-layer using B2H6as a dopant source. The ?-doped p-layers deposited with trimethylboron (TMB) and triethylboron (TEB) as new boron sources were characterized. It was found that the boron layers obtained with TMB by photo-CVD contain a large amount of carbon atoms which degrade the solar cell performance. Carbon contamination was suppressed both by the plasma CVD method with a gas mixture of TMB, H2and He and by the photo-CVD method with TEB.

We have grown high-conductivity textured ZnO films by the photo-MOCVD method using DEZ (diethylzinc) and H2O as reactant gases. It was found that the UV light irradiation during the growth was very effective in the improvement of electron mobility. The improvement of the electron mobility could be caused by the chemisorption of the oxygen at the grain boundaries. The boron-doped ZnO films were also grown by photo-MOCVD using B2H6as dopant gas. The resistivity of the films grown with UV irradiation was one order of magnitude less than that grown without UV irradiation, and the minimum resistivity of 6.8×10-4?·cm was obtained by the photo-MOCVD method.

Epitaxial Si films were successfully grown by the mercury-sensitized photochemical vapor deposition (photo-CVD) method with SiH2Cl2at a substrate temperature of as low as 200° C. The electrical and optical properties of the obtained films were characterized by Hall measurement, IR and Raman spectroscopy and transmission electron microscopy. Furthermore, the n-type doping was carried out by the addition of PH3gas, and the electron concentration was varied from 1016cm-3to 1018cm-3by varying the PH3/SiH4gas ratio. It was found from the experiments that there was a strong correlation between the SiH2Cl2and H2flow rates for obtaining the epitaxial Si films at a low temperature.

To improve the accuracy in caustic measurement, the effect of parallax with 30 lenses of a Cranz-Schardin-type camera on the determination of caustic diameter Dwas experimentally evaluated using a single-edge-notch-type model specimen. Correction factors for the transverse diameter of caustics on an image plane were obtained. These factors were taken into account in the determination of the velocity effect on the dynamic stress intensity factor KIDof PMMA during fast crack propagation. It is shown that the hysteresis in the KID-\dotacurves was similar for larger and smaller initial curves except at velocities higher than 400 m/s.

?-Doping of carbon into GaAs by metal-organic molecular beam epitaxy (MOMBE) has been studied in detail using trimethylgallium (TMG), Ga and As4. TMG was adsorbed in the wide range of temperatures from 20°C to 550°C during growth interruption. It is shown that Ga deposition after TMG adsorption is effective for obtaining a high peak hole concentration. This is in contrast to the case with As evaporation, which drastically reduces the peak carrier concentration. The dependence of peak hole concentration on the TMG adsorption temperature shows a specific feature. The highest peak hole concentration is 4×1019cm-3for a TMG adsorption temperature of 20°C.

Epitaxial Si films have been successfully grown by the photochemical vapor deposition process using the mixture of SiH4, SiH2F2and D2gases at temperatures from 200 to 475°C. Using H2as diluting gas, the epitaxial Si films were obtained at temperatures from 200 to 350°C. However, the upper limit of the growth temperature was raised about 100°C (from 350 to 475°C) by substituting D2for H2as the diluting gas. Surface morphology and crystallinity were also improved with D2. Furthermore, we carried out heavy phosphorous doping with D2and obtained a film with an electron concentration of 1×1021cm-3.

Textured ZnO films have been grown by metalorganic chemical vapor deposition (MOCVD) using diethylzinc (DEZ) and H2O as reactant gases. It was found that the surface morphology of films was strongly dependent on the substrate temperature. For the low substrate temperature of 150°C, the surface consists of uniformly sized tetrapodlike features. These undoped films have a high transparency in a wide wavelength range from 400 nm to 1400 nm. The low-resistivity ZnO films have also been succesfully grown using a dopant gas of B2H6diluted with H2. A sheet resistivity as low as 10 ?/was obtained.

Formation kinetics of polycrystalline CuInSe2films in selenization of Cu/In/Se stacked layers was studied using Raman spectroscopy. Raman spectra of the films clearly show a structural change of the film at elevated temperatures. It is concluded that Cu is selenized preferentially at low temperatures around 200°C and that the CuInSe2phase is formed at temperatures above 250°C.

ZnTe films were grown on GaAs substrates by atomic layer epitaxy using the molecular beam epitaxy technique. We investigated the growth rate per cycle as a function of beam intensities of Zn and Te at the substrate temperature of 250°C and obtained the self-limiting growth of 0.5 monolayer per cycle, independent of Zn or Te beam intensity in the selected ranges.

A GaAs pseudo-heterojunction bipolar transistor with a heavily carbon-doped base grown by metalorganic molecular beam epitaxy was fabricated, and the highest dc current gain of 1.7 was obtained, which evidences band-gap narrowing in the base. However, hole injection from the base to the emitter still cannot be ignored, and the use of a heavily carbon-doped InGaAs base is proposed to improve transistor characteristics.