ABSTRACT
Electron Energy Loss Spectroscopy (PEELS) in the extreme-low loss energy range and Energy Loss Near Edge Spectroscopy (ELNES) were carried out in a cold FEG-STEM to study GaN (0001), AlGaN, and AIN. Using cross sectional samples, a study has been performed of the variation of near-band gap states when stepping the e-beam parallel to the c direction along threading dislocations and in the perfect material. In addition, the aforementioned techniques, along with Energy Dispersive X-rays (EDX), have been employed to study the substrate-thin film interface regions. For the first time, we found evidence of impurities gettering at dislocations and showed how this method can be used to measure small changes in near band-gap related energy values in a spatially resolved fashion.
