Submount for light emitting/receiving device

A submount for a light emitting/receiving device, comprising:

• a mounting surface on which a light emitting/receiving device is mounted;
• a device-side opening which is provided in the mounting surface and through which light inputted to or outputted from the light emitting/receiving device passes;
• an outer opening provided in a face facing the mounting surfaces, said device-side opening and side outer opening being open to the device which is spaced from the device-side opening;
• a reflecting surface which adjoins the device-side opening and the outer opening and which is formed parallel with a specified crystal orientation face so as to reflect the light between one side on which the light emitting/receiving device is provided and another side on which the outer opening is opened;
• a dielectric film which is formed on the mounting surface and which surrounds the device-side opening;
• an electrode which is formed on the dielectric film and an inner end portion of which is spaced laterally at a specified distance from the device-side opening but does not extend laterally toward said device-side opening beyond said dielectric film;
• and
• a brazing material layer between and securing together the device and said inner end portion, said layer not extending to said opening when molten due to said lateral spacings.