Electrical characterization of defect states in local conductivity domains in ZnO:N,As layers

摘要: P- and n-type conductivity domains in dual-doped ZnO:As+N layers grown by metal organic vapor phase epitaxy on GaN–sapphire templates were electrically microcharacterized scanning capacitance microscopy (SCM) surface potential (SSPM) techniques with respect to their defect states. The p-type found be dominated two acceptors thermal activation energies of about 80 270 meV, as observed transient SCM scans at different temperatures. Optically excited SSPM revealed defect-to-band transitions 400, 459, 505 nm omnipresent both domain types well a shallower transition 377 exclusively the regions. According similar energy levels, optical 400 are assigned acceptor states, whereby 80-meV is probably responsible for conversion from n- regions domains.