The importance of the contamination particle control in state of the art electron device production, such as a semiconductor, is increasing more than ever. Particle counter has been widely used as the technique of measuring particles suspended in the liquid phase and the gaseous phase. ITRS has been showing concretely the number concentration of particles, which should be controlled, in air, gas and liquid in contact with wafers. First, the leading-edge technology of the liquid-borne particle counter is shown, since the request about particle control in liquid of ITRS is considered as the typical information on a market trend. Meanwhile, the level of the particle contamination in process, such as a vacuum process does not have the shared roadmap. However, since TFT-LCD and PV which industrial scale has expanded rapidly, needs a high speed film deposition at a large substrate, the particle contamination control in vacuum process has been attracting attention. So the technique of the particle measurement in PECVD reactor is shown as an example of the particle measurement in vacuum processes which are expected as new application of a particle counter technology. Finally, a subject common to the measurement technique which uses a light scattering phenomenon as a principle, and the directivity of its improvement is shown.

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  Test wafers are regularly used for monitoring the daily chamber conditions from the viewpoint of particle contamination in the semiconductor manufacturing equipment. Since the number of particles contaminating on a wafer often varies, the particle management by the sampling inspection only observes the situation at the moment. In situ particle monitor (ISPM) is developed as a technique for real time monitoring the particle. This time, ISPM was installed in the mass production 300 mm plasma etcher at the bypass exhaust line connected with a dry pump. The ISPM count at one cleaning cycle and the correlation with the mass production yield were investigated. The ISPM count takes the decreasing tendency immediately after maintenance. The production yield also has fallen with the repeated etching processes. It is able to monitor the yield decrease by managing the logarithmic index of the ISPM count.

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  Reducing both pump-down time and particle contamination in load lock chambers is important for the vacuum apparatus to improve productivity in semiconductor device manufacturing. In this study, particles that became detached from the chamber wall and flew up in the chamber during pump-down were observed with an in-situ particle monitor. Particles attached to a wafer surface were also counted using a wafer inspection system. The dependence of the number of flying particles on pump-down time constant τ agreed with the dependence of the number of particles attached to the wafer surface on τ. Thus, it was deduced that the in-situ particle monitor was useful for determining a suitable pump-down speed. Furthermore, when the pump-down speed was increased, fast particles were generated, which damaged the fine photoresist patterns.

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  Aerosol Deposition Method (ADM) is a new technology of ceramics film deposition. Using this method, we can deposit various ceramics thick films (one-several hundreds micrometer of thickness) on metal, glass and ceramics substrates. It's normal temperature process and doesn't require any heating expedient. Films have dense nano-crystalline structure, good adhesion on many substrate and good mechanical properties. For several years we have been developing this process. In this paper, overview of application to semiconductor manufacturing equipment parts by ADM was reported.

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  For stable semiconductor device manufacturing, the management of the smaller size of particles must be required since the latest device is getting highly integrated with pattern dimension shrinkage year by year.
  Most of particles attached on the wafers will be generated under the processing at the process equipment.
  To maintain the high-yield of the semiconductor devices, particle number/size of all process equipment should be monitored. And it will be important to determine the root cause of the particle generation and the measure as soon as possible if particle number over the control limit is detected.
  On this article, the latest techniques about particle detection on the wafers, efficient observation/review, and particle element analysis are introduced.

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  Stored beams in electron storage rings are susceptible to the trapping of a micron-sized dust particle. This phenomenon, called “dust trapping”, can significantly reduce the beam lifetime and occasionally lasts for tens of minutes, whereby the experiments utilizing accelerator beams can be severely disrupted. Numerous observations and theoretical analyses have led to some credible models, for instance, the stably trapped dust particle reaches thermal equilibrium between energy transfer from the electron beam and cooling by heat radiation. Recently the trapped dust was found to be observable by video cameras, and the visual observation is becoming a promising method for the dust-trapping research.

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  Reactions of hydrogen with solid surfaces have become ones of the important subjects in the environment-related technologies, for example, as applications to the fuel cells. We review theoretical studies of hydrogen reactions on Cu(100), Cu(110) and Pd(111) surfaces and subsurfaces by quantum simulation method based on the first-principles calculations. By this method, we can obtain eigenenergies and three-dimensional eigenfunctions of hydrogen atomic motion in the vicinity of the surface. Based on the obtained results, we discuss quantum effects on excitation of hydrogen motion and diffusion within the surface and between the surface and subsurface. We especially focus on isotope effects arising from binding properties in the potential energy surfaces for the hydrogen atomic motion.

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  A principle and applications of “hydrogen microscope” have been described. An electron stimulated desorption (ESD) method is useful tool to detect hydrogen on the solid surfaces using a time-of-flight technology with slow electron pulsed-beam. Scanning ESD Ion microscope (SESDIM) is simply called the “hydrogen microscope” which highly sensitive to detect proton.
  After description of some characteristics and applications of the ESD, imaging method and examples of hydrogen 2-D maps are introduced as results of hydrogen storage alloys and ion implanted device.

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  This paper presents elastic recoil detection analysis (ERDA) of hydrogen (H) located near surface regions using low, medium and high energy ion beams. In particular, cruicial points and application of the ERDA using MeV He⁺ ions with high reliability and probing depth of ∼1 μm are described in detail. The ERDA by means of a low energy time-of-flight technique and by medium energy Ne⁺ impact provides a powerful tool for quatitative and highly sensitive detection of H on solid surfaces. The Si(111)-1×1 terminated by H and the reduced TiO₂(110) surface exposed to water moelcules are analyzed quantitatively using medium energy Ne⁺ ions.

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  A constant pressure type flowmeter was developed to generate precise gas flow for calibrations of vacuum gauges by an orifice flow method and standard leaks by a comparison method. The flow rate is derived from the constant pressure and the volume reduction rate. For accurate measurement of volume reduction, a relation of the bellows length and its volume was measured as mounted in the flowmeter. Volume change at 25 mm was 32.19 ml. Measurement uncertainty is 0.24%. In order to keep the pressure in the main chamber constant, a reference chamber was installed to detect pressure change in the main chamber by the differential pressure between two chambers. Pressure was kept constant within 0.01% during the operation of flowmeter. By changing the initial pressure in the flowmeter from 0.16 Pa to 5000 Pa for nitrogen, flow rate of 4×10⁻⁹∼8×10⁻⁴ Pa m³/s was generated with a relative standard uncertainty of 5.7%∼0.36%. A gas is effused through a metal capillary attached to the main chamber. Repeated conductance measurements of the capillary for 540 days showed that the gas flow rate measurements was stable within∼0.1%.

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