PURPOSE: To make it possible to mass-produce the captioned stem and to improve its quality without requiring expensive hard glass by drilling holes at mounting positions of encapsuled wires and an exhaust tube on a glass piece obtained by cutting plate glass, and by mounting the encapsuled wire and exhaust tube in said hole.

CONSTITUTION: A circular disc 7 is made by cutting plate glass 6, and a hole 10 for mounting an exhaust tube 9 is drilled on the center O of said disc and 4 pores 11 for inserting encapsuled wires at point symmetrical positions with respect to said center O. Then, a glass made exhaust tube 9 is fused while butted to the hole 10 part of the disc 7. Here, the encapsuled wires 3 are inserted into the pores 11, and tentatively fixed by means of glass solder or glass of low melting point. Then it is entered in an electric furnace 12 and heated, and fused and fixed while the disc 7 and exhaust tube 9 are subjected to elimination of strain. Hereby, it is possible to mass-produce the stem and to improve the yield thereof without dispersion of the quality level.