The feasibility of X-ray lithography in fine pattern replication process is reviewed by discussing the points such as resolution, exposure time, exposure area, alignment accuracy and so on. Applications to the replication of patterns without alignment, or to small area exposure are now possible and successfull. In high accuracy replication including multiple mask alignment, there remain some problems to be solved. One of them is the serious allowance of wafer-mask gap variation. Improvements of X-ray source and resist become more important for high speed replication.
The purpose of this study is to investigate a U bend open channel meter. The measuring principle of this flowmeter is systematically developed in this paper on the basis of Bernoulli's theorem and Euler's equation. It is shown theoretically that the liquid head at any point in the fiowmeter is exclusively a function of the distance from the bend axis. The apparatus used in the experiment is an open channel meter with a rectanqular cross section, the depth, the inner radius and the outer radius being 60cm, 50cm, 60cm, respectively. The results of, experiments show that obtained flowrates at a measureing position of the inflow angle of 90 degrees agree approximately with those obtained by a Venturi tube flowmeter.
Some results of observations on the bubble domain texture found in a homeotropically aligned texture of large pitch cholesterics are reported. Bubble domains are generated by electro-hydrodynamic turbulence in the narrow range of pitch and cell thickness combination. They are erased by applying a. high-frequency AC electric field. A possible structure of the bubble domain is a ring of a single striped-domain on which model various properties of the bubble domain can be explained. Bubble domains which are generated in a cross point of narrow stripe-shaped row and column electrodes (100×100μm2) can be transported from corner to corner in the cross point on application of a week DC field; non-uniform fields at the fringe of the electrodes playing an important role for the transportation.
The paper reports a singnal-analyzing system in a laser Doppler microscope made to explore the flow velocity in an extremely small area having a diameter less than 10μm, and its measuring errors. This signal-analyzing system consists mainly of the time-to-voltage converter and the analog computer of multiplication and division and is based on the principle of measuring the wave period in the beat signal from which its frequency can be determined by calculating the inverse value of the wave period. Various errors appearing in the present signal-analyzing system have been investigated together with their causes and their reduction method. As a result, it becomes clear that the measuring accuracy is largely affected by both the amplitude limitation of beat signals and the properties of electric filters employed to remove the pedestal component of beat signals.