PURPOSE: To join objects together while keeping a grain shape to the possible minimum level, and provide heart pacemaker electrodes whose porosity is secured by filling granular materials such as Pt metal in recessed parts of a first jig, and baking them in a specific temperature range in the atmosphere.

CONSTITUTION: After granular materials of Pt metal or Pt alloy are filled in recessed parts 2 arranged at constant intervals in large numbers on an upper surface of a first jig 1, a second jig 5 having pores 4 bored at the same pitch with the recessed parts 2 is placed on the first jig 1. Next, after shafts 6 of Pt metal or Pt alloy are inserted in the respective pores 4, a third jig 7 is placed on the second jig 5, and the shafts 6 are pushed in the granular materials in the recessed parts 2, and are stabilized, and heights are properly arranged. Afterwards, they are baked at 1200°C to 1500°C in the atmosphere by an electric furnace, and desired electrodes are obtained. Ceramics is preferable as the first jig, and Al2O3 or ZrO2 is used. Preferably, Pt or Pt-Ir 10wt.% alloy having a particle diameter of 20 to 50μm is used as the granular materials.