Secondary Ion Mass Spectrometry to Measure Residual Impurities in Aluminum Nitride Single Crystals
EMSL Project ID
32197
Abstract
The relative concentrations of the major residual impurities found in three aluminum nitride single crystals grown by the sublimation-recondensation method will be analyzed by secondary ion mass spectroscopy. The residual impurities and their complexes with point defects (primarily aluminum vacancies) cause detrimental absorption of light below the band gap of AlN. The purpose of this study is to gather preliminary information on how the choice of three crucible materials, tungsten, boron nitride, or graphite, affects the relative concentrations of the main residual impurities; carbon, oxygen, silicon, and boron. Information from this study will be used to refine the crystal growth process, to eliminate the unwanted absorption in the crystals. Ultimately, high quality AlN single crystals will be employed as substrates for group III nitride semiconductor devices for solid state lighting, ultraviolet light radiation detectors, and chemical sensors.
Project Details
Project type
Limited Scope
Start Date
2008-10-10
End Date
2008-12-05
Status
Closed
Released Data Link
Team
Principal Investigator