Accession Number : ADA190438
Title : NRL 1.3 Micron High Power Single Element Laser Diode.
Descriptive Note : Monthly rept. no. 9.
Corporate Author : TRW SPACE AND TECHNOLOGY GROUP REDONDO BEACH CA APPLIED TECHNOLOGY DIV
PDF Url : ADA190438
Report Date : Oct 1987
Pagination or Media Count : 4
Abstract : As discussed in last month's technical report (Monthly Report No. 8, September 1987), an examination of the characteristics of devices which we have made indicate several problems. Slope efficiencies (nd) are low, averaging between 0.20 and 0.30 mW/mA range. Also, the far-field characteristics of most devices show multiple-lobed structures, indicative of interference of radiation from several sources. There are some devices with stable, smooth far-field patterns, but they are a minority. To analyze this problem, devices with no facet coatings had their far-field characteristics measured and then underwent SEM analysis of the device's cross-section as viewed from the front-facet. The SEM micrographs were attached to the far-field plots and a comparison was made across several devices. The SEM micrographs reveal extraneous and irregular crystal growth (of the epitaxial layer which forms the active region) along the walls of the V-channel. SEM micrographs of every device which showed this anomalous crystal growth on the walls of the V-channel correspond to far-field patterns which are characterized by multiple lobes.
Descriptors : *COATINGS, *CRYSTAL GROWTH, *EPITAXIAL GROWTH, *PATTERNS, ANOMALIES, CROSS SECTIONS, EFFICIENCY, FAR FIELD, LAYERS, PLOTTING, REGIONS, SLOPE, STABILITY, WALLS
Subject Categories : Lasers and Masers
Distribution Statement : APPROVED FOR PUBLIC RELEASE