Submount Technologies for Realizing High Speed Laser Diode

• Main Authors: Hung-wei Tseng, 曾竑維
• Other Authors: San-liang Lee
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/58764835482856861305

碩士 === 國立臺灣科技大學 === 電子工程系 === 100 === The thesis focuses on the development of a thermal-managed sub-mount platform for high-speed semiconductor laser applications. As the high-speed laser usually operates at relatively higher current bias in order to have a stable and single-frequency lasing output, however, the heating issue causes the wavelength shift, output power drop and the decay of its high-speed performance. Therefore, thermal management is of vital importance for laser packaging. The use of p-side down configuration for laser packaging is able to conduct the heat efficiently. The use of ground-signal-ground (GSG) planar electrode configuration to have impedance match is also important. In order to avoid the current leakage, the growth of a thin dielectric film between the electrode and the silicon sub-mount is necessary. We have established a 3ω measurement setup to measure the thermal conductivity of the dielectric film in order to find the best material for both electrical isolation and heat dissipation. On the other hand, the optical coupling between packaged laser and output fiber/waveguide is also challenging. We have fabricated input/output U-grooves to passively align the fiber to the optical output field. However, the uncertainty of bonded laser chip in vertical direction is the main roadblock. By designing the area ratio between the etched trenches and the solders, we have successfully reduced the bonding gap between the sub-mount and the laser chip, thus opening the possibility of the proposed platform for practical applications.