Current mapping of GaN films by conductive atomic force microscopy

Pomarico, A. A.; Huang, D.; Dickinson, J.; Baski, A. A.; Cingolani, R.; Morkoç, H.; Molnar, R.
March 2003
Applied Physics Letters;3/24/2003, Vol. 82 Issue 12, p1890
Academic Journal
Conductive atomic force microscopy has been used to investigate the local conductivity in hydride vapor-phase epitaxy and molecular-beam epitaxy GaN films, focusing on the effect of off-axis facet planes. We investigated two different types of samples, in which the facet planes were either present on the perimeters of as-grown islands, or on the edges of etch pits created by post-growth chemical etching. The results show that crystallographic planes tilted with respect to the c-plane growth direction show a significantly higher conductivity than surrounding areas. The n-type (or p-type) samples required a negative (or positive) sample bias for current conduction, consistent with the formation of a Schottky barrier between the metallized atomic force microscope tip and sample. The time dependence of this enhanced conductivity was different for the two types of samples, possibly indicating different conduction mechanisms.


Related Articles

  • Fractal character of the distribution of surface potential irregularities in epitaxial n-GaAs (100). Torkhov, N. A.; Bozhkov, V. G. // Semiconductors;May2009, Vol. 43 Issue 5, p551 

    The fractal geometric properties of the relief of the surface potential of a heavily doped n+-GaAs (100) wafer are studied by Kelvin’s method of atomic force microscopy. The average fractal dimensionalities determined by the triangulation method ( D f), the method of horizontal cross...

  • Characterization of AIII BV epitaxial layers by scanning spreading resistance microscopy. SZYSZKA, ADAM; SCIANA, BEATA; RADZIEWICZ, DAMIAN; MACHERZYNSKI, WOJCIECH; PASZKIEWICZ, BOGDAN; TLACZALA, MAREK // Optica Applicata;2011, Vol. 41 Issue 2, p281 

    One of the electrical characterization techniques of semiconductor structures with nanometer spatial resolution is scanning spreading resistance microscopy (SSRM). The applicability of SSRM technique for characterization of GaAs structures with n-type doping fabricated by metalorganic vapour...

  • Ultrahigh vacuum atomic force microscope study of 10-30 nm scale GaAs ridge structure formation.... Koshiba, S.; Tanaka, Ichiro // Applied Physics Letters;2/17/1997, Vol. 70 Issue 7, p883 

    Investigates the evolution of GaAs (gallium arsenide) ridge structure formation by molecular beam epitaxy (MBE) on a patterned substrate using an ultrahigh vacuum atomic force microscope. Characteristics of the size fluctuation of the ridge; Mechanisms of the ridge formation; Features of the MBE.

  • Determination of the fractal dimension for the epitaxial n-GaAs surface in the local limit. Torkhov, N. A.; Bozhkova, V. G.; V.Ivonin, I.; Novikov, V. A. // Semiconductors;Jan2009, Vol. 43 Issue 1, p33 

    Atomic-force microscopy studies of epitaxial n-GaAs surfaces prepared to deposit barrier contacts showed that major relief for such surfaces is characterized by a roughness within 3–15 nm, although “surges” up to 30–70 nm are observed. Using three independent methods...

  • In situ, atomic force microscope studies of the evolution of InAs three-dimensional islands on GaAs(001). Kobayashi, N.P.; Ramachandran, T.R.; Chen, P.; Madhukar, A. // Applied Physics Letters;6/3/1996, Vol. 68 Issue 23, p3299 

    Examines the size evolution of molecular beam epitaxy-grown strained indium arsenide three-dimensional (3D) islands. Stages of the size evolution of 3D islands; Use of ultrahigh vacuum atomic force microscopy; Observation on the lateral size dispersion.

  • Correlation between the Energy of SiGe Nanoislands and Their Shape and Size. Valakh, M. Ya.; Dzhagan, V.N.; Krasil'nik, Z.F.; Lytvyn, P.M.; Lobanov, D.N.; Mozdor, E.V.; Novikov, A.V.; Yukhymchuk, V.A.; Yaremko, A.M. // Physics of the Solid State;Jan2004, Vol. 46 Issue 1, p67 

    The total energy of self-assembled SiGe nanoislands on a silicon substrate is investigated theoretically as a function of their geometric and physical parameters. It is demonstrated that the growth temperature and the silicon content in nanoislands affect the minimum of their energy. The results...

  • Faceting during GaAs quantum dot self-assembly by droplet epitaxy. Heyn, Ch.; Stemmann, A.; Schramm, A.; Welsch, H.; Hansen, W.; Nemcsics, Á. // Applied Physics Letters;5/14/2007, Vol. 90 Issue 20, p203105 

    Strain-free GaAs quantum dots (QDs) are grown in a self-assembled fashion by applying Ga droplet epitaxy. The QDs are studied using electron diffraction and atomic force microscopy. Two distinct regimes are observed for the QD shape. QDs whose volume exceeds approximately 3×105 Ga atoms are...

  • Influence of the degree of order of InGaP on its hardness determined using nanoindentation. Zakaria, A.; Fetzer, C. M.; Goorsky, M. S. // Journal of Applied Physics;Oct2010, Vol. 108 Issue 7, p074908 

    Spontaneous atomic ordering takes place during metal-organic vapor phase epitaxy when certain semiconductors alloys start forming long-range arrangements different from their standard lattice unit cells. In the case of InGaP, a zincblende semiconductor, the ordered CuPt(B) structure consists of...

  • Deformations in (Al,Ga)As epitaxial layers wafer bonded on dissimilar substrates. Jenichen, B.; Kaganer, V. M.; Riedel, A.; Kostial, H.; Gong, Q.; Hey, R.; Friedland, K.; Ploog, K. H. // Journal of Applied Physics;2/15/2001, Vol. 89 Issue 4, p2173 

    Deformations in heteroepitaxial layer stacks of AlGaAs/GaAs grown on GaAs are measured by triple crystal diffractometry before epitaxial liftoff and after subsequent wafer bonding on various substrates (GaAs, glass, Si, and LiNbO[sub 3]). The tetragonal deformation present in the as-grown layer...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics