PACKAGING TECHNOLOGY FOR SURFACE MOUNTABLE, LOW-PROFILE FIBER OPTIC TRANSMITTER AND RECEIVER

The subscriber network and trunk line network requires more economical and smaller optical Transmitter/Receiver (Tx/Rx) than before. These T x/Rx are essential components of fiber optic transmission systems. We have developed low-cost and high-density packaging technology by integ rating the passive alignment, which is high accuracy Laser Diode (LD) mounting technology, and the bared IC mounting technique into one pack age. The developed technology can achieve high productivity and compac t size in consideration of using the high accuracy LD mounting machine with popular IC assembly and electric components surface mounting sys tems. In addition, this packaging technology offers the advantage to u sers of these Tx/Rx. That is, the structure makes it possible to reflo w soldering in the same way as conventional surface mount electrical c omponents. A simple receptacle structure and a conductive adhesive con nection method bring advantages, as the fiber pigtails are detachable from the housings during the board assembly and the conductive adhesiv e connection can withstand reflow soldering temperature. In this paper , a newly developed packaging technology is presented for a novel opti cal Tx and Rx pair which measures 10 x 26 x 3 mm(3) each. This paper a lso proposes a high thermal conductivity package structure to solve th ermal issue. It can operate these Tx/Rx over -40 to +85 degrees C ambi ent temperature.