A rotary plunger vacuum pump has high displacement efficiency and robust structure. The pumps are used in hard process of general industry. The demand of saving energy in industry is increasing these days. Rotary plunger vacuum pumps are required to suppress the energy as well. Therefore, the approach of the energy reduction for the pumps has begun. The pump's power consumption could be explained by two factors. One is the mechanical loss and the other is the compression work. We developed a rotary plunger vacuum pump which implement low frictional structure. The low frictional structure allowed low viscosity vacuum oil. With efficient driving by controlling rotation speed, this pump reduced energy by 30% compared to the conventional pump. Beyond that we introduced the way of energy saving by reduction of the compression work.

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  For dry vacuum pumps, typically used for chemical vapor deposition (CVD) and Etching process in semiconductor factory, the durability of byproduct deposition and /or corrosion is very important. And also energy saving is one of the key factor on this application for cost ownership stand point.
  Our ``Model EV-M'' dry pumps have achieved significant enhancement for saving energy consumption, and have incorporated various countermeasures against byproduct deposition and corrosion, like optimized internal temperature profile and material selection. With these, both significant saving energy and process durability can be achieved under the use of the harsh duty condition such as CVD and Etching process.
(Note: EV-M is Ebara's model code)

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  Turbomolecular pump is featured by mainly two performance, they are pumping speed (or volume flow rate) and ultimate pressure, which mean how fast and how lower the pressure pump can evacuate a vacuum chamber, respectively. The measurement methods of these pump's characteristics are specified in the JAPANESE INDUSTRIAL STANDARDS (JIS B 8328), and specific numerical values are provided by turbo molecular pump's manufacturers.
  These days, the turbomolecular pump that has the ability to handle larger rate of gas under low vacuum is required in the field of semiconductor and liquid-crystal display panel device manufacturing, for example. This kind of pump's performance characteristics are expressed by the terms such as the maximum throughput, maximum working pressure, maximum backing pressure, critical backing pressure and so on. But recently, the definitions in the manufacture's specifications do not always coincide each other, and sometimes seems different from relevant standards.
  In this report, we refer to the current standards with regard to turbomolecular pumps performance characteristics and related terms, and refer to concerns about definitions of the maximum backing pressure, ultimate pressure and maximum throughput which seem especially inaccurate in terms of the definition of terms and way of expression.

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  We fabricated Ni films on an Acrylonitrile-Butadiene-Styrene resin (ABS) using unbalanced magnetron sputtering assisted by inductively coupled plasma. The effect of ion irradiation controlled by target DC power P_T and magnetic flux density toward the substrate B_C on the Ni film structures was investigated. Argon ion emission intensity I_ArII near the substrate increased with P_T and B_C. In addition, substrate current I_S drastically decreased above P_T=500 W. We observed that ion irradiation was enhanced by increasing B_C above P_T=500 W. From x-ray diffraction measurement, the crystallite size t₍₁₁₁₎ increased with the effect of ion irradiation. A minimum film resistivity of 1.4×10⁻⁵ Ωcm was measured for P_T=600 W and B_C=5 mT. We conclude that controlling the effect of ion irradiation is effective for high quality Ni film formation on ABS.

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  The evolution of target “race track” erosion was evaluated experimentally during the conventional DC magnetron sputtering of metal targets with different Ar gas pressure environments. At gas pressures of 0.38, 0.5, and 1.0 Pa, an aluminum or copper target was sputtered at a DC discharge power of 100 W. At time intervals of several hours, the target was taken out of the chamber and its erosion profile was measured with a height gauge. As the sputtering erosion of the target proceeded, the erosion track diameter was almost the same in all sputtering conditions, whereas the track width (full width at half maximum: FWHM) showed quite different behaviors depending on the gas pressure. At 0.38 Pa, the FWMH increased slightly with increasing sputtering time. On the other hand, at 1.0 Pa, the FWMH decreased with increasing sputtering time.

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  This fourth lecture of “Basics of Vacuum measurement from viewpoint of Metrology” introduces the long-term stability of vacuum gauges, such as capacitance diaphragm gauges (CDGs), high accuracy pressure gauges, spinning rotor gauges (SRGs), ionization gauges (IGs), and quadrupole mass spectrometers (QMSs). The data includes results obtained by laboratory experiments, stability of transfer standards for international comparisons, and calibration experiences of customer gauges by both national metrology institutes and vacuum gauge manufacturers. It is important to understand general trends of their long-term stabilities for reliable vacuum pressure measurements.

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