| 摘要 |
PURPOSE:To facilitate convergence of a laser beam without using a lens by providing monolithic integration of concave mirrors in a DFB laser. CONSTITUTION:A grating 2 for distributed reflection is formed on an N-type InP substrate 1 and an N-type InGaAsP waveguide layer 2, a P-type InGaAsP active layer 3, a P-type InP cladding layer 4 and a P-type InGaAsP cap layer 5 are formed successively on the grating 2 to form a material wafer. A BH laser wafer is composed of this material wafer. Holes 6, which have partially circular cross sections and side walls vertical to the wafer surface, are formed in the wafer and, at the same time, electrodes 8 and 9 are provided on the top and bottom surfaces of the wafer to form a DFB laser. With this constitution, as a laser beam 10 emitted from the laser 15 is focused on one point, alignment can be achieved easily by providing the end surface 12 of an optical fiber 11 at that point. |
