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A compact ignition system for antenna-excited microwave discharge lamps filled with extremely high pressure mercury has been investigated using 2.45 GHz microwave power from a solid-state microwave generator. The properties of the present lamps were compared with those of conventional lamps ignited by AC electric power. It was found that the emission spectra were almost the same as each other. As a consequence, antenna-excited microwave discharge can be applied to the ignition for so-called superhigh-pressure mercury lamps, inside which the pressure is around 200 to 300 atm during lamp ignition.

In this paper, the color control of xenon-mercury fluorescent lamps through the use of both internal (longitudinal direction) and external (radial direction) electrodes is described. The inner surface of the cylindrical lamp was fully or partially coated with a mixture of two kinds of color phosphors. One of the phosphors is excited by the resonance radiation of mercury, and the other is excited by the vacuum ultraviolet (VUV) radiation of xenon. The color of the lamp light can be changed from that of one phosphor to that of the other phosphor by varying the mixture ratio of longitudinal discharge (LD) by the internal electrodes to radial discharge (RD) by the external electrodes. The wide color range in the Commission Internationale de l'Elairage (CIE) chromaticity diagram is obtained as follows: (x,y)=(0.262,0.129)-(0.533,0.280) for a blue-red lamp, (x,y)=(0.513,0.390)-(0.285,0.625) for an orange-green lamp and (x,y)=(0.139,0.147)-(0.166,0.548) for a blue-green lamp. The luminances are about 1000 cd/m2 for these lamps.

Organic thin-film transistors (OTFTs) with tailored liquid sources of HfO2 as a high-κ insulator were investigated. To investigate the effect of UV irradiation, two types of light source were tested. The contact angles of water and polycrystalline condition of a pentacene were systematically changed and the resultant OTFT characteristics were also changed. The field-effect mobilities and on–off ratios obtained using a high-pressure mercury lamp and a deep-UV lamp as irradiation sources were 0.035 and 0.10 cm2 V-1 s-1, and 24 and 3 ×103, respectively.

In this paper, we examine the research and discovery of a highly efficient electrode material which we called yttrium-dihydride. This material is effective in a cold cathode lamp which is illuminant. The composition of crystal yttrium-dihydride (YH x ) film was compared from the optical reflectivity. A cold cathode lamp with a tube of 63 mm length and an outside diameter of 2.6 mm was fabricated for the experiment, and the glow-discharge voltage was measured to evaluate the performance of the electrode using the YH x film. The lamp current was set at 5 mA for the measurement. The lamp voltage in the nickel electrode for the reference lamp was 220 V. The lamp voltage in the YH x electrode was 169 V. The yttrium-dihydride is revealed to be a more highly emission efficient material. In addition, the lamp voltage remained constant for more than 7,500 h, thus demonstrating that this material is extremely stable.

A GaAs surface-cleaning method using UVO3 treatment was developed. The UVO3 treatment involves two processes: GaAs surface oxidation and oxide removal. Surface oxidation is performed by using a mercury lamp at high temperature, such as 180°C. GaAs oxide is removed by NH4OH solution dipping. Spectroscopic ellipsometry and X-ray photoelectron spectroscopy (XPS) study showed that thermally unstable As oxides exist on a non-treated surface; however, surface GaAs oxides are almost completely removed by this treatment. This cleaning method was applied in the field effect transistor (FET)-gate-formation process and, consequently, Schottky leakage current was significantly reduced.

Brighter and electrodeless light sources are developed by introducing the electron cyclotron resonance (ECR) effect into the discharge area. In the present proof-of-principle demonstration, a microwave source with a frequency of 2.45 GHz, and a maximum power of 1 kW is used. A mercury lamp placed inside the microwave cavity is immersed in a uniform magnetic field, B. At B = 875 G, which satisfies the ECR condition, the light intensity is increased by 28% at an incident microwave power of 800 W. Short-wavelength components are effectively improved relative to long ones.

The effect of oxidation due to ultraviolet (UV) irradiation in air on diamond thin film synthesized by hot-filament chemical vapor deposition (CVD) has been investigated. A low-pressure mercury lamp is used as the UV light source. With UV irradiation, removal of graphite contained in the film begins at a temperature of 350° C due to the oxidation. This temperature is 250° C lower than that reported to yield the same effect without UV irradiation. UV irradiation enables the selective removal of graphite while maintaining the idiomorphic structure of diamond. It is clarified that direct UV irradiation on the film is critical in this process.

A negative-film diffraction grating was made by taking a photograph of a pattern drawn using an XY-plotter connected to a personal computer. To check the performance of the negative-film grating, a simple monochromator system was built with it. Five spectrum lines in the light from a mercury lamp were observed with the monochromator system.

Fundamental studies of a new type of ozonizer, which has no dielectrics between main metal electrodes and has a circuit called charge transfer, have been carried out. The rate constant k 1 for the reaction of O+O2+O2→O3+O2 has been measured through absorption measurements using the 253 nm line of a mercury lamp in He/O2 mixtures at atmospheric pressure.

Silicon can be directly nitrided at relatively low temperature under NH3 flow with UV-irradiation from a low-pressure mercury lamp. The typical thickness of film is 6.2 nm for nitridation of 1 h at 800°C. The thickness is saturated with an increase in nitridation time. The Auger electron intensity of nitrogen is about two times larger than that of oxygen at the surface of the film. The apparent peak of IR absorption by the Si-N bond is seen at a wave number of 835 cm-1.

Static charge elimination of a charged matter can be achieved using a low pressure quartz mercury lamp. Positive charge elimination is by photoelectrons emitted from the quartz surface of the lamp and negative charge elimination by photoelectrons emitted from the charged matter. This technique can be used in the case where inflammable gases are present and be used even under vacuum conditions.

Silica glasses were exposed to glow-discharge plasma of various kinds of gases or to UV light from a low-pressure mercury lamp, and were investigated by ESR. In the case of the plasma exposure, the E' centers are created by UV light emitted from the plasma with photon energy smaller than the optical gap. After a long period of plasma exposure, the density of the E' centers decreases when hydrogen atoms supplied from H2 plasma and/or produced by dissociating OH species in the surface layer move into the inner part of the sample. In the case of the UV-light exposure, illumination time dependence of the E' center density varies with the OH concentration, suggesting that hydrogen plays a role in reducing the E' centers.

A tungsten-carbon(W/C) X-ray multilayered mirror was prepared by photoinduced chemical vapor deposition (photo-CVD) using a low-pressure mercury lamp and an argon-fluoride (ArF) excimer laser. The 40% reflectivity of this mirror was measured using a small-angle X-ray diffractometer with Cu-Kα radiation. This reflectivity is lower than the theoretical reflectivity of 80%. From observations of the transmission electron micrograph from this multilayered mirror, it seems that the reduction of the reflectivity was caused by the indistinct interfaces of the diffused films, and by the roughness of the films introduced by partial crystallization of the tungsten films.

As implanted Si was annealed using halogen and mercury lamps whose lights primarily have, respectively, infrared and ultraviolet regions. Annealing time necessary for fully electrically activating the implanted As in the mercury lamp annealing was shorter than that in the halogen lamp annealing, when the light emitted from the two lamps was of the same intensity. This was due to the difference in intensity of the light absorbed into the implanted Si between the lamps used at the beginning of annealing.

Photoelectrons are emitted from the quartz surface of an ultraviolet lamp under atmospheric air conditions, and the lamp behaves like an electron emitter. The lamp used in the present experiment is 4 W and has light emission peaks at 185 nm and 254 nm. With this lamp, the emission current of the order of 10-9 A is produced in atmospheric air. This photoemission phenomenon is of great importance to charge elimination of charged matter.

We have constructed a simple ac sputtering apparatus in which the growing film surface can be irradiated with light from a low-pressure mercury lamp. Yb-Ba-Cu-O thin films were irradiated by UV light at various steps of film preparation. The light irradiation was found to improve the superconductivity of the films, providing a promising method for decreasing the processing temperature of high-T c superconducting oxide films. The pronounced irradiation effect at the post-annealing step suggests that the UV light primarily works to accelerate the incorporation of oxygen into the films.

Silicon dioxide films have been prepared from monosilane and oxygen gases using a low-pressure mercury lamp. The deposition rate is increased with UV irradiation and the activation energy is reduced to as low as 0.22 eV. The contribution of the 254 nm light to the deposition is concluded to be very small. The refractive index of the deposited film is 1.44∼1.46. The infrared absorption peaks related with Si–H bonding do not appear in the photo-CVD film.

The effect of irradiation of ultraviolet (UV) light from a low pressure mercury lamp on the copper electroless plating process has been investigated. Both enhancement of the plating rate and the opposite effect of suppression are obtained. It is possible to make copper film pattern by these effects with resolving power of 50 µm.

Silicon nitride films have been formed using a photo-CVD apparatus with a microwave-excited deuterium lamp. The BHF etching rate, 40–70 Å/ min, deposited at 320°C is lower by less than one-tenth than that deposited using a conventional low-pressure mercury lamp, indicating formation of a high density film. The deposition rate has been enhanced dramatically from 13 Å/min to 100 Å/min by incorporating the photo-ionization assisted effect, which is brought about by an ionization of a substrate surface, ions formed by collisions of reactant gases with photoelectrons and photo-ionized ions.

Polycrystalline ZnS:Mn films with good crystallinity are grown by photo-assisted MOCVD using dimethylzinc and diethylsulphide. The growth temperature is decreased from 550 to 400°C by photo-irradiation (high-pressure mercury lamp) and no dead layer results. Patterned ZnS films can also be grown by this method. Thin film electroluminescent devices fabricated using these films have lower threshold voltages.

A simple and sensitive optical interferometer system is developed to extend the lower limit of measurable electron densities for time varying plasmas. This technique, which can eliminate the effect of mechanical vibrations of the building floor and/or the drift, is tested and compared with that of an 8 mm microwave measurement. The electron density decay from 1015 cm-3 down to 4×1013 cm-3 for a plasma length of 20 cm is detected by a wave of 0.5463µ from a mercury lamp.