| 摘要 |
PURPOSE:To prevent die bonded solder from coming into contact with a junction exposed to a chip side especially when assembling J/D required for low temperature characteristics. CONSTITUTION:Barrier layers 7a and 7b are formed on both surfaces of a sub-mount board 10. Furthermore, an AuSn eutectic solder layer 8 is partially formed on the barrier layer 7b where an AuSn eutectic solder layer 9 is installed to the whole surface of the barrier layer 7b. This construction makes it possible to inhibit the amount of solder which swells out to a chip side to a satisfactory extent, thereby providing a high reliability laser element which reduces an initial failure attributable to soldering short to a junction and which is virtually immune to the effect of solder in an environmental test. |
