| 摘要 |
PURPOSE:To obtain a high coupling efficiency when coupled with a singlemode fiber and absorb light leaked from an active layer to restrict laser oscillation, by coupling an absorption layer to the entire side surface, except for a light emitting end surface, of an active lay with reduced width and constituting a current blocking layer including this absorption layer. CONSTITUTION:An n-InP layer 4 is etched with a 2 deg.C etchant of (HCl+H2O), a P-InGap layer 3 is overetched with a liquid mixture of K3Fe(CN)6, KOH and H2O so as to reduce its width to 2-5mum to form an active layer. Again a p-Inp layer is etched with the 2 deg.C (HCl+H2O) etchant so as to leave the p-InP layer 2 on the entire surface of a p-InP substrate 1. Then an SiO2 film 5 is removed with a HF liquid to form a double-hetero junction structure consisting of the active layer and two clad layers pinching it. The projections of an n-InP layer 2 are removed by a liquid phase epitaxial growth method, on which an n-InP layer 6, p-InGaAsP layer 7 and p-InP layer 8 are grown in that order to form a block layer. |
