NOVELTY - Fluorine or fluorine compound gas having concentration of 90% or more is supplied to plasma generation portion (31) of remote plasma source (30) with pressure of 100 Pa or less. High-frequency electric power is supplied to remote plasma source, the plasma generation portion generates plasma and fluorine active species from fluorine or fluorine compound gas under pressure of 100 Pa or less. The fluorine active species are supplied to deposition chamber (10) and cleaned.    USE - Remote cleaning of deposition chamber used for chemical vapor-deposition apparatus for manufacturing liquid crystal display device and organic electroluminescent display device for personal computer, and solar cell panel.    ADVANTAGE - The method enables efficient and economical remote cleaning of deposition chamber even at low electric power, without environmental pollution.    DETAILED DESCRIPTION - A silicon compound is deposited using a remote plasma source. The plasma generated by plasma generation portion is diffused in a deposition chamber. A remote cleaning system is provided such that the plasma generation portion of remote plasma source spaced apart from the deposition chamber, and provided such that the remote cleaning system does not have influence toxic to structure fixture or substrate in deposition chamber. Fluorine or fluorine compound gas having concentration of 90% or more as gas for cleaning is supplied to plasma generation portion of remote plasma source with pressure of 100 Pa or less. High-frequency electric power is supplied to remote plasma source, the plasma generation portion generates plasma and fluorine active species from fluorine or fluorine compound gas under pressure of 100 Pa or less. The fluorine active species are supplied to deposition chamber and cleaned.    DESCRIPTION OF DRAWING(S) - The drawing shows the block diagram of the chemical vapor-deposition apparatus. (Drawing includes non-English language text)    Chemical vapor-deposition apparatus (1)    Deposition chamber (10)    Remote plasma source (30)    Plasma generation portion (31)    Gas supply system (34)