Title :
Characterization of buried heterostructure lasers by scanning capacitance microscopy
Author :
Anand, S. ; Kallstenius, T. ; Stoltz, B. ; Smith, U. ; Landgren, G.
Author_Institution :
Lab. of Semicond. Mater., R. Inst. of Technol., Stockholm, Sweden
Abstract :
Zn-Fe interdiffusion is an important issue in InP-based buried heterostructure lasers that utilise Zn for p doping and Fe for the semi-insulating layers. In this work, cross-sectional scanning capacitance microscopy (SCM) is used to characterise these laser structures. The capability of the SCM technique to analyse such complex devices is demonstrated. The SCM images (on as-cleaved samples) show that diffusion of Zn into the semi-insulating layer is significant and extends as far as 0.7 μm. Similar values (about 0.5 μm) were obtained by atomic force microscopy (AFM) investigations on samples etched with a dopant selective etchant. Further, the SCM images are shown to give additional useful information on the active doping levels in the different layers and the location of the (electrical) p-n junctions. Finally, the mechanisms for the contrast in the SCM images are discussed
Keywords :
III-V semiconductors; atomic force microscopy; capacitance; chemical interdiffusion; indium compounds; optical microscopy; optical scanners; optical testing; semiconductor device testing; semiconductor doping; semiconductor lasers; 0.5 mum; 0.7 mum; Fe semi-insulating layers; InP-based buried heterostructure lasers; SCM images; SCM technique; Zn-Fe; Zn-Fe interdiffusion; active doping levels; as-cleaved samples; atomic force microscopy; buried heterostructure lasers; cross-sectional scanning capacitance microscopy; dopant selective etchant; electrical p-n junctions; etched; laser structures; p doping; scanning capacitance microscopy; semi-insulating layer; Atomic force microscopy; Capacitance; Etching; Iron; Laser theory; P-n junctions; Semiconductor device doping; Semiconductor lasers; Surfaces; Zinc;
Conference_Titel :
Indium Phosphide and Related Materials, 1999. IPRM. 1999 Eleventh International Conference on
Conference_Location :
Davos
Print_ISBN :
0-7803-5562-8
DOI :
10.1109/ICIPRM.1999.773636