Fabrication of p-n junctions in ZnO by arsenic ion implantation followed by annealing in atomic oxygen

• Published in: Inorganic materials Vol. 43; no. 7; pp. 714 - 719
• Main Authors: Rogozin, I. V., Georgobiani, A. N., Kotlyarevsky, M. B.
• Format: Journal Article
• Language: English
• Published: 01.07.2007
• ISSN: 0020-1685; 1608-3172
• DOI: 10.1134/S0020168507070084

We report the properties of p-n junctions produced in ZnO films by As super(+) ion implantation followed by annealing in atomic oxygen. The starting films, n-ZnO , were grown by magnetron sputtering on amorphous SiO sub(2) substrates. As shown by x-ray diffraction, the c axis of ZnO is perpendicular to the film surface. The resistivity of the p-ZnO layer is 30-35 Omega cm, carrier mobility 1-2.5 cm super(2)/(V s), and hole concentration 3 x 10 super(18) cm super(-3). The arsenic and gallium concentrations are 2.5 x 10 super(19) and 1 x 10 super(18) cm super(-3), respectively. The arsenic profile is Gaussian in shape, as shown by secondary ion mass spectrometry. Current-voltage data attest to the presence of an i-layer and to recombination in the space charge region. The barrier height evaluated from current-voltage and capacitance-voltage data is about 3.4 eV, which is comparable to the band gap of ZnO. The electro-and photoluminescence spectra of the junctions show bands at 440 and 510 nm. The 510-nm emission is typical of as-grown n-ZnO films. The 440-nm band is attributable to donor-acceptor recombination.