Microwave plasma processing device and plasma processing gas supply member

A microwave plasma processing device comprising:

• fixing means for fixing a substrate as a processing target on a central axis in a plasma processing chamber;
• exhausting means for depressurizing an inside and outside of the substrate;
• a metal processing gas supply member which is present in the substrate and forms a reentrant cylindrical resonating system along with the plasma processing chamber;
• and microwave introducing means for introducing a microwave into the plasma processing chamber to perform processing,
• wherein a microwave sealing member is provided at a substrate-holding portion of the fixing means,
• a connection position of the microwave introducing means is located at a node of an electric field intensity distribution formed on the processing gas supply member by introducing the microwave,
• a distance (D) between the microwave sealing member and a surface of the fixing means positioned in the plasma processing chamber is 0 to 55 mm, and
• a distance (H) between the microwave sealing member and the connection position of the microwave introducing means satisfies a relationship of the following expression:
• H=L−(·n2λ/2+λ/8−3)+β(mm)
• where n2 is an integer satisfying n2≦n1−1, λ is a wavelength of the microwave, β is a fluctuation band caused due to a dimension or the like of the substrate and is ±10 mm, and L is a distance between the microwave sealing member and the end portion of the processing gas supply member and satisfies the following relationships:
• A. in case of 0≦D<20
• L=(n1λ/2+λ/8)−3+α
• B. in case of 20≦D≦35
• L=(n1λ/2+λ/8)−(−0.060D2+4.2D−57)+α
• C. in case of 35<D≦55
• L=(n1λ/2+λ/8)−(−0.030D2+2.1D−21)+α
• where n1 is an integer which is not smaller than 1, λ is a wavelength of the microwave, and α is a fluctuation band in consideration of an influence and the like of the substrate on an electric field and is ±10 mm.