| 摘要 |
1500156 Semi-conductor lasers RCA CORPORATION 26 Aug 1975 [6 Sept 1974] 35177/75 Headings H1C and H1K In a stripe electrode double heterostructure semi-conductor laser, the P-type semi-conductor region 24 in which the stripe electrode 46 is provided is electrically and thermally connected to a heat sink 58 by a soft ductile material 60 such as indium or a gallium or mercury alloy, while the radiation-emitting ends 20 of the semi-conductor are sealed against the ingress of moisture. For sealing, the end surfaces of the semi-conductor may be coated with an electrical insulating material 56 such as an aluminium oxide, or the laser may be encapsulated in a transparent housing or a housing provided with windows. The semi-conductor is epitaxially grown in an oxygen-free atmosphere, and comprises a GaAs substrate 28, an N-type GaAs layer 30, an N-type GaAlAs layer 32 providing an optical confinement boundary 40, a P- or an N-type GaAlAs active layer 26, a P-type layer 34 providing an optical confinement boundary 42 and a P-type GaAs layer 36. The active layer 26 may be doped with silicon or germanium, and the other layers doped with tellurium, tin, or germanium. Spaced insulating strips of SiO are formed on layer 36, and a zone 38 of the layer between the strips is highly doped by zinc diffusion to provide a conductive stripe region on which a compound electrode 46 is formed. Preferably electrode 46 comprises a titanium or chromium layer 48, a platinum or nickel layer 50, and a gold layer 52. An electrode 54 of the same character or of a single metal such as tin is provided on the substrate 28. A semi-conductor laser body is formed by cleaving from a larger wafer on which end surface protective coatings 56 have previously been applied. |
