Title :
In situ monitoring and control for MBE growth of optoelectronic devices
Author :
Jackson, Andrew W. ; Pinsukanjana, Paul R. ; Gossard, Arthur C. ; Coldren, Larry A.
Author_Institution :
Dept. of Mater., California Univ., Santa Barbara, CA, USA
fDate :
6/1/1997 12:00:00 AM
Abstract :
Improved control over layer thickness has been realized using optical interference techniques such as reflectance spectroscopy. It is now common to observe spectra of distributed-Bragg-reflector (DBR) mirrors during growth to make corrections for growth rate drifts. Real-time optical flux monitoring (OFM) by atomic absorption allows precise layer control by measuring group III fluxes continuously during growth. The flux information can be used to operate growth shutters and to control effusion cell heaters in a feedback loop. Improved substrate temperature measurement by diffuse reflectance spectroscopy (DRS) allows precise measurement of substrate temperature. DRS is not subject to the same errors encountered in pyrometer or thermocouple measurements of substrate temperature
Keywords :
atomic absorption spectroscopy; distributed Bragg reflector lasers; interference spectroscopy; molecular beam epitaxial growth; optoelectronic devices; reflectometry; semiconductor growth; substrates; surface emitting lasers; temperature measurement; thickness control; thickness measurement; MBE growth; VCSEL; atomic absorption; control; diffuse reflectance spectroscopy; distributed-Bragg-reflector mirrors; effusion cell heaters; feedback loop; flux information; group III fluxes; growth rate drifts; growth shutters; in situ monitoring; layer thickness; optical interference techniques; optoelectronic devices; precise layer control; pyrometer measurements; real-time optical flux monitoring; reflectance spectroscopy; substrate temperature; substrate temperature measurement; thermocouple measurements; Atom optics; Atomic measurements; Interference; Monitoring; Optical control; Optical feedback; Reflectivity; Spectroscopy; Temperature measurement; Thickness control;
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/2944.640637
