The techniques for manufacture of In2O3 films which have the most excellent properties for applications as transparent conductors and heat mirrors are reviewed, and reported mainly on the vacuum deposition method developed by the authors. The best result can be obtained by electron-beam evaporation of In2O3 mixed with SnO2, WO3 or MoO3. The deposited films have resistivity of 2×10-4Ω•cm, visible transmittance of about 90% and IR reflectance of 90%. The one doped with WO3 or MoO3 show steep step-up of IR reflection at λp of about 2μm because of its large Hall mobility near 100cm2/V•s. Besides, the techniques concerning 3-layer anti-reflection coatings together with MgF2 and CeF3 films and the deposition onto a large sized glass plate are described.
The effective minority carrier lifetime has been studied in low dose F+, B+, BF+, BF2+ and P+ ion implanted p-type silicon, using laser diode as the carrier injection source (1 mmø, spot). The effective lifetime of an ion implanted region decreases with increase of ion dose and energy. The dependence of the effective lifetime Δ (1/τ) on ion dose, ion energy and mass of the implanted ions can be formulated as a function of the total knock-on number induced by ion implantation. The coefficient of Δ (1/τ) in its relation to the ion dose depends slightly on the n acceptor concentration in silicon substrate for the concentration range from 3.5×1014cm-3 to 2.0×1015cm-3.
It is well known that electron emission properties of negative electron affinity (NEA) surface depend upon the cleanliness of the surface to an atomic level as well as its activation treatment with caesium and oxygen. Observations are reported on photoemission images of the activated surface in Si and GaAsP cold cathode, obtained by scanning the surface with He-Ne laser spot. It was found that the optimum activation procedure for photoemission from the cleaned area is not consistent with that from the uncleaned surrounding area and was also shown that the optimum activation condition for the cold cathode emission corresponds to that of the optimum photoemission from the active section of the cold cathode. Finally, we demonstrate that these observations are useful for the evaluation of activation process of the NEA cathode. Resolution of the photoemission images was about 10 Am and was limited by the size of the laser beam spot.
The influence of oblique deposition on the growth rate, etching rate and structure of the SiO2 thin film deposited by a planar magnet-ron sputtering method was investigated, It was found that the etching rate of the SiO2 film by NH4F-HF-CH3COOH solution in-creased rapidly with increase of the incidence angle, whereas the growth rate was almost constant in the whole range of the incidence angle examined. Furthermore, it was found that the films sputter deposited at incidence angles greater than 60 degrees were found to have a columnar grain structure.
An organic phosphor has been impregnated in the micropores of anodic oxide film on aluminum to produce a fluorescent aluminum panel. Aluminum hydroxide was suspended in a solution of sulfosalicylic acid, in which anodically filmed aluminum was immersed at room tem-perature for 24 his. The impregnated film was then heat-treated in the air at 300°C for 10min. The fluorescence intensity was markedly increased by this heat-treatment. The fluores-cence spectrum showed blue to violet band, the emission peak being 395-405 nm. The optimum conditions of obtaining the strongest fluorescence were determined.
An electrostatic field imposed on a dielectric surface was applied as a condenser lens for an electron beam exposed to the dielectric surface. A procedure was devised for obser-ving the electron diffraction pattern from a microscopic object.
The present status of researches on epitaxial growth of ZnS and its applications to electronic devices are reviewed. The epitaxial growth technique is found to be useful to prepare highly ordered ZnS crystals free from twins, grain boundaries, stacking faults, etc. because of the low growth-temperatures. Various methods for the preparations of ZnS eptaxial films on singlecrystalline substrates, such as vacuum deposition, sputtering, sublimation, chemical transport, chemical vapor deposition, molecular-beam epitaxy and liquid phase epitaxy are explained. Crystal structures and electrical and optical properties of the epitaxial ZnS films are discussed, and some device applications of the epitaxial crystals are described briefly.
This article surveys the restricted fields with the properties related to isolated negative ions. The conception on the electron affinity and its determination methods are explained, especially the determination methods which have been developed recently, photodetachment by laser and charge exchange by cesium atoms are described relatively detailed. The formation processes of the negative ions are classified by three main processes, that are electron captures, ion-pair fomation and charge exchanges, and these individual processes are explained briefly. The exposition are also included the temperature effects for the negative ion formation by dissociative resonance electron capture. Finally, as the problem should required near future, the formation procedures of the very intense deuterium negative ions for the negative ion based neutral beam injection into the devices of the magnetically confined fusion are reviewed.
Software technologies indispensable for finer pattern generation electron beam lithography are reviewed in this paper. Corrections for electron beam deflection distortion, proximity effect and pattern distortions owing to wafer warpage and overlapped exposure are seen to be necessary. This paper mainly addressed computing correction techniques for proximity effect and electron beam deflection distortion. The basic principles of pattern data processing are described. Proximity effect correction is also clarified, with classification into inter-proximity, or the resultant interconnection of adjacent patterns, and intra-proximity, the rounding of pattern corners. For electron beam deflection distortion correction, the inverse mapping of distortion function is solved. As pattern data manipulation techniques, arithmetic operations on polygons with flexible chain-link data-structure are conducted.
Recent developments of electron beam lithography systems, chiefly electron beam delineators, are reviewed. After various types of the machines are classified, the explanations are made about principal elements of the machines, the control system, electron gun, electro-optical column and the sample stage putting emphasis on the factors which govern the accuracy of the fine patterns. The drawing time, one of the key factors for practical use, is analyzed and the compromization between speed and accuracy is discussed introducing the authors' estimation about the optimization of variable shaped beams as an example. The experimental efforts of drawing ultimately fine lines by electron beams are also described.