Submount manufacturing method of the optical module, and the sub-mount having the same

The preparation of the submount is facilitated, also improve the production efficiency. The first electrode layer 12, are stacked on the surface of the submount substrate 11. Side 122 of the first electrode layer 12 is formed on the submount substrate side 112 of 11 substantially the same plane. Side 122 of the first electrode layer 12 is the connecting surface for making electrical connection to the first electrode layer 12. By sufficiently increasing the thickness of the first electrode layer 12, it is possible to increase the area of ​​the side surface 122 sufficiently. Thus, for example, wire bonding can be performed using this aspect 122. Further, it is possible with a plug 16 to protect the components such as the optical element 14.