METAL SEAL, FLUID CONTROL APPARATUS AND SEALING METHOD

The invention provides a metal seal, a fluid control apparatus and a sealing method, that can prevent fine scratches from being easily produced by slipping of the metal seal and has high close contactperformance with surfaces. The metal seal is sandwiched between first and second flat surfaces. The seal includes a first/second end surface opposite to the first/second flat surface, respectively. The first end surface includes paired first protrusions formed displaced in a radial direction of the metal seal and have dihedral angles contacting the first flat surface, and the second end surface includes a second protrusion formed inward of one first protrusion and outward of the other first protrusion in the radial direction, and has a dihedral angle contacting the second flat surface, and paired third protrusions that are respectively formed inward and outward of the second protrusion and whose highest points to which perpendicular distances from a reference plane including the dihedralangles of the paired first