NOVELTY - An ozone gas condensed unit (30) concentrates ozone gas. A dissolution unit (50) dissolves in water the concentration ozone gas obtained by ozone gas condensed unit and obtains ozone water. A cleaning unit (70) cleans a target object with the ozone water obtained in the ozone gas dissolution unit. A valve control unit controls the pressure of the concentration ozone gas dissolved in the water. A waste gas pump reduces the pressure of the concentration ozone gas.    USE - Apparatus for cleaning electronic component. Uses include but are not limited to semiconductor wafer, liquid crystal, solar cell, organic electroluminescent, and printed circuit board.    ADVANTAGE - The high concentration ozone gas is obtained easily and quantity of ozone which escapes in air out of ozone water is restrained low. The density of ozone water which reaches surface of target object can be kept high so that cleaning efficiency is improved. The density of ozone water is stabilized by control which adjusts pressure of concentration ozone gas. The rapid decomposition of ozone is reliably prevented to ensure safety of ozone gas dissolution unit.    DETAILED DESCRIPTION - The apparatus includes a diluent gas supply unit which adds the oxygen gas for dilution to concentration ozone gas supplied to the ozone gas dissolution unit. A diluent gas flow-control unit controls the flow volume of oxygen gas added to the concentration ozone gas based on pressure of concentration ozone gas in ozone gas dissolution unit. The concentration ozone gas is supplied with respect to several ozone gas dissolution unit. Each concentration ozone gas supply line top supplies the concentration ozone gas to several ozone gas dissolution unit respectively. A pressure regulation unit adjusts the pressure of the concentration ozone gas at the side of the ozone gas dissolution unit. A flow volume adjustment unit adjusts the flow volume of concentration ozone gas at side of the ozone gas dissolution unit. A supply-pressure adjustment unit adjusts the pressure of the concentration ozone gas supplied from the ozone gas condensed unit more upstream than several pressure regulation unit and flow volume adjustment unit.    DESCRIPTION OF DRAWING(S) - The drawing shows the block diagram of the electronic component cleaning apparatus. (Drawing includes non-English language text)    Electronic component cleaning apparatus (1)    Ozone gas condensed unit (30)    Dissolution unit (50)    Cleaning unit (70)    Ozone water generating apparatus (71)