Title :
A novel one step integration of edge-emitting laser diode with micro-elliptical lens using focused ion beam direct deposition
Author :
Fu, Yongpi ; Bryan, Ngoi Kok Ann
Author_Institution :
Sch. of Mech. & Production Eng., Nanyang Technol. Univ., Singapore
fDate :
2/1/2002 12:00:00 AM
Abstract :
An edge-emitting laser diode (LD) integrated with a microlens on its emitting surface for the purpose of collimating and fiber coupling is introduced in detail in this paper. A micro-elliptical lens is adopted for the integration in terms of divergence angle in both parallel and transverse directions. The lens with dimensions of 50 μm×30 μm×4 μm is microfabricated on the emitting surface of the laser diode with operating wavelength of 635 nm directly by focused ion beam (FIB) deposition function. The SiO2 deposition is realized by programming of the FIB machine. It is shown by test results that the focused spot size in the parallel and transverse propagation directions are 7.9 and 9.1 μm (at site of 1/e2), respectively, and the coupling efficiency of the compact and miniaturized system can reach as high as 71%. Measured far-field angles (full angle) with the microlens in both parallel and transverse directions are 2.2° and 1.2°, respectively. Compared with the original divergence angles of 31° and 14° without the micro-elliptical lens, they were greatly reduced by this method
Keywords :
focused ion beam technology; integrated optoelectronics; microlenses; optical collimators; optical fabrication; optical fibre couplers; optical focusing; semiconductor lasers; 30 micron; 4 micron; 50 micron; 635 nm; 7.9 micron; 71 percent; 9.1 micron; FIB deposition; FIB machine programming; SiO2; SiO2 deposition; collimation; coupling efficiency; divergence angle; edge-emitting laser diode; emitting surface; far-field angle; fiber coupling; focused ion beam direct deposition; focused spot size; lens dimensions; micro-elliptical lens; microfabrication; microlens; propagation directions; single step integration; Collimators; Diode lasers; Ion beams; Lenses; Microoptics; Optical coupling; Optical propagation; Surface emitting lasers; Surface waves; System testing;
Journal_Title :
Semiconductor Manufacturing, IEEE Transactions on
