The impact of CF4 plasma treatment on the transport properties of the two dimensional electron gas (2DEG) in AlGaNGaN heterostrustures has been studied. Systematic Hall measurements of the plasma-treated samples show a large degradation in mobility and sheet concentration, which can be partially recovered with short-duration rapid thermal annealing. Further annealing progressively degrades both mobility and sheet concentration. Secondary ion mass spectrometry of the heterostructure reveals accumulation of fluorine at the AlGaNGaN interface close to the 2DEG channel as a result of annealing. Following our systematic electrical and analytical studies of the behavior of fluorine incorporated into the heterostructure epilayer due to bombardment, a vacancy-mediated postannealing redistribution of fluorine has been proposed.
ASJC Scopus subject areas
- Physics and Astronomy(all)