Press Release Back Number(2005)

Development of ultra-high-density ozone generation technology
-Ozone generation achieved at world's highest density levels of 400g/Nm3 -

November 7, 2005
Chubu Electric Power Co., Inc.

Chubu Electric Power Co., Inc. and Mitsubishi Electric Corp. (President: Tamotsu Nomakuchi; address: Tokyo Building, 7-3, Marunouchi 2-chome, Chiyoda-ku, Tokyo) have jointly developed an ultra-high-density ozone generation technology for use primarily in electronic component cleaning processes at semiconductor and liquid-crystal plants.
Plans call for the commercialization and sale of ozone-generation equipment based on this technology from December 2005 by Toshiba Mitsubishi-Electric Industrial Systems Corp.


Composed of three oxygen atoms, ozone gas offers oxidation capabilities superior to chlorine. It is already widely used for various applications, including disinfection, deodorization, and decoloration.
Ozone is generated by passing oxygen gas between two plate electrodes and applying high-voltage electricity. However, creating high-density ozone requires minimization of the discharge gap (gap length) between these electrodes.


This technology reduces this gap from the scale of 100mm*1 possible with previous technology to 50mm, at no additional cost. It does so by applying heat and pressure to fix the two electrodes in place, which makes it possible to dramatically increase ozone density*2 from a figure of 210 g/Nm3 possible using earlier technology to 400g/Nm3-the highest achieved to date anywhere in the world.


*1 1mm: 1/1000 millimeter

*2 Density (g/Nm3) refers to grams of ozone gas in 1m3 (at 0°C and 1 atmospheric pressure) of an ozone (O3) and oxygen (O2) compound gas.


The cleaning process for electronic components such as semiconductors involves use of large volumes of chemical solutions such as sulfuric acid and chlorine. The purchase and disposal of such chemicals is extremely costly. In these applications, using ozone in place of these solutions reduces plant costs.
Additionally, since ozone breaks down into oxygen after use, no chemicals or other substances are required for disposal. Nor does it produce harmful byproducts, making it an environmentally sensitive cleaner.


Key characteristics of this high-density ozone-generation technology

  • • The world's highest level of achieved density:
    Generates high-density ozone at densities up to 400 g/Nm3, rated density: 350 g/Nm3.
    (Earlier technology generates ozone at densities up to 300 g/Nm3, with rated density of 210 g/Nm3.)
  • • Generates ozone at high efficiency levels:
    Can generate 1.5 times the ozone produced using current technology at the same levels of power consumption.