Growth and conduction mechanism of As-doped p-type ZnO thin films deposited by MOCVD

Abstract As-doped p-type ZnO thin films were fabricated by metal organic chemical vapor deposition (MOCVD) after in situ annealing in a vacuum. The p-type conduction mechanism was suggested by the analysis of X-ray photoelectron spectroscopy and ultraviolet photoemission spectroscopy. It was found that most of the As dopants in p-ZnO thin films formed As Zn –2V Zn shallow acceptor complex, simultaneously, carbon impurities also played an important role in realizing p-type conductivity in ZnO. Substitutional carbon on oxygen site created passivated defect bands by combining with Ga atoms due to the donor-acceptor pair Coulomb binding, which shifted the valence-band maximum upwards for ZnO and thus increased the hole concentration.

[1]  Krueger,et al.  First-principles calculation of the electronic structure of the wurtzite semiconductors ZnO and ZnS. , 1993, Physical review. B, Condensed matter.

[2]  G. Lo,et al.  p-type conduction in unintentional carbon-doped ZnO thin films , 2007 .

[3]  D. Hoyt,et al.  Acceptors in ZnO nanocrystals , 2011 .

[4]  Sean Li,et al.  Size dependence of Zn 2p 3∕2 binding energy in nanocrystalline ZnO , 2006 .

[5]  Sheng Chu,et al.  Electrically pumped ultraviolet ZnO diode lasers on Si , 2008 .

[6]  D. Choi,et al.  Correlation of band edge native defect state evolution to bulk mobility changes in ZnO thin films , 2010 .

[7]  Z. Yin,et al.  As-doped p-type ZnO films by sputtering and thermal diffusion process , 2006 .

[8]  Zhifeng Shi,et al.  The luminescence of ZnO film grown on GaAs interlayer by PA-MOCVD , 2011 .

[9]  M. McCluskey,et al.  Nitrogen is a deep acceptor in ZnO , 2011 .

[10]  E. Alves,et al.  Direct evidence for As as a Zn-site impurity in ZnO. , 2005, Physical review letters.

[11]  J. Ramos-Barrado,et al.  Unraveling the conduction mechanism of Al-doped ZnO films by valence band soft x-ray photoemission spectroscopy , 2005 .

[12]  L. H. Van,et al.  Room-temperature ferromagnetism in carbon-doped ZnO. , 2007, Physical review letters.

[13]  S. Russo,et al.  Roles of carbon in light emission of ZnO , 2010 .

[14]  E. Solomon,et al.  Electronic structures of active sites on metal oxide surfaces: definition of the copper-zinc oxide methanol synthesis catalyst by photoelectron spectroscopy , 1993 .

[15]  Miin-Jang Chen,et al.  Stable p-type ZnO films grown by atomic layer deposition on GaAs substrates and treated by post-deposition rapid thermal annealing , 2011 .

[16]  Qifeng Zhang,et al.  Electrically driven ultraviolet lasing behavior from phosphorus-doped p-ZnO nanonail array/n-Si heterojunction , 2009 .

[17]  Rong Zhang,et al.  Carbon clusters in N-doped ZnO by metal-organic chemical vapor deposition , 2008 .

[18]  Anderson Janotti,et al.  Why nitrogen cannot lead to $p$-type conductivity in ZnO , 2009 .

[19]  M. Gendry,et al.  Oxides on GaAs and InAs surfaces: An x-ray-photoelectron-spectroscopy study of reference compounds and thin oxide layers. , 1994, Physical review. B, Condensed matter.

[20]  C. H. Park,et al.  Doping by large-size-mismatched impurities: the microscopic origin of arsenic- or antimony-doped p-type zinc oxide. , 2004, Physical review letters.

[21]  S. Lau,et al.  Room temperature deposition of p-type arsenic doped ZnO polycrystalline films by laser-assist filtered cathodic vacuum arc technique , 2007 .

[22]  Y. Liu,et al.  Hole transport in p-type ZnO films grown by plasma-assisted molecular beam epitaxy , 2006 .

[23]  C. Walle,et al.  Hydrogen passivation effect in nitrogen-doped ZnO thin films , 2005 .

[24]  Z. G. Wang,et al.  Comparison of valence band x-ray photoelectron spectrum between Al–N-codoped and N-doped ZnO films , 2006 .

[25]  Congting Sun,et al.  Formation of Al-doped ZnO films by dc magnetron reactive sputtering , 2001 .

[26]  Jian Sun,et al.  Arsenic-doped ZnO films fabricated on silicon substrates by pulsed laser ablation , 2008 .

[27]  S. Chua,et al.  Annealing effects on electrical and optical properties of ZnO thin-film samples deposited by radio frequency-magnetron sputtering on GaAs (001) substrates , 2007 .

[28]  Electrically pumped lasing from p-ZnO/n-GaN heterojunction diodes , 2012 .

[29]  Tae-Seok Lee,et al.  Excitonic ultraviolet lasing in ZnO-based light emitting devices , 2007 .

[30]  Roger G. Williams,et al.  An investigation of control mechanisms of the excitonic behavior in reactively sputtered ZnO on (0001) Al2O3 , 2006 .

[31]  Z. Ren,et al.  The effects of thermal annealing on ZnO thin films grown by pulsed laser deposition , 2000 .

[32]  Dong Lim Kim,et al.  Investigation on the p-type formation mechanism of arsenic doped p-type ZnO thin film , 2006 .

[33]  A. Rohatgi,et al.  Grain‐boundary characterization of ZnO varistors by positron annihilation spectroscopy , 1989 .

[34]  Zhifeng Shi,et al.  Electroluminescence of the p-ZnO:As/n-ZnO LEDs grown on ITO glass coated with GaAs interlayer , 2011 .