Full text loading...
(Color online) (a) In situ (1 ×3) RHEED patterns of InN during the growth of a thin InN epilayer on AlN(0001)/Al2O3, showing the evidence of In polarity. (b) In situ (3 ×3) RHEED patterns during the growth of a GaN low-temperature buffer layer for an InN/AlN/GaN /Al2O3 structure, showing the evidence of N polarity. (c) X-ray diffraction profiles, including InN(0002), GaN(0002), and AlN(0002) peaks of thin InN/AlN(0001)/Al2O3 (top) and InN/AlN/GaN/Al2O3 (bottom) heterojunction samples.
(Color online) (a) Schematic drawings of the sample structures, including spontaneous polarizations, polarization-induced interface sheet charges, spontaneous-polarization-induced changes in the binding energy separation between Al 2p and In 4d core-levels, and atomic arrangements between In/Al- and N-polar InN/AlN heterojunctions. (b) Al 2p and In 4d core-level spectra of In/Al- and N-polar InN/AlN heterojunctions obtained at an incoming photon energy of 380 eV.
Photoelectron spectroscopy measured binding energy differences between cation core-level and valence band maximum (E CL − EV ) for InN and AlN bulk epilayer samples, as well as cation core-level binding energy separations (ΔE CL) and valence band offsets (ΔEV ) for InN/AlN heterojunction samples with different crystal polarities.
Article metrics loading...