<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The work investigates an increase of the density of free charge carriers in the sub-surface region of p-GaN by adding p-type dopants into the Ni-O layer of an Au/Ni-O metallization structure. We have examined electrical properties and concentration depth profiles of contact structures Au/Ni-Mg-O/p-GaN and Au/Ni-Zn-O/p-GaN, thus with magnesium and zinc as p-type dopants. The metallization layers were deposited on p-GaN by DC reactive magnetron sputtering in an atmosphere with a low concentration of oxygen (0.2 at%). The contacts were annealed in N2 . We have found that the structures containing magnesium or zinc exhibit lower values of contact resistivity in comparison with otherwise identical contacts without Mg or Zn dopants. In our opinion, the lower values of contact resistivity of the structures containing of Mg or Zn are caused by an increased density of holes in the sub-surface region of p-GaN due to diffusion of Mg or Zn from the deposited doped contact layers.</p></abstract>

The work investigates an increase of the density of free charge carriers in the sub-surface region of p-GaN by adding p-type dopants into the Ni-O layer of an Au/Ni-O metallization structure. We have examined electrical properties and concentration depth profiles of contact structures Au/Ni-Mg-O/p-GaN and Au/Ni-Zn-O/p-GaN, thus with magnesium and zinc as p-type dopants. The metallization layers were deposited on p-GaN by DC reactive magnetron sputtering in an atmosphere with a low concentration of oxygen (0.2 at%). The contacts were annealed in N2 . We have found that the structures containing magnesium or zinc exhibit lower values of contact resistivity in comparison with otherwise identical contacts without Mg or Zn dopants. In our opinion, the lower values of contact resistivity of the structures containing of Mg or Zn are caused by an increased density of holes in the sub-surface region of p-GaN due to diffusion of Mg or Zn from the deposited doped contact layers.

Improving the ohmic properties of contacts to P–GaN by adding p–type dopants into the metallization layer

Slovak University of Technology, Faculty of Electrical Engineering and Information Technology, Ilkoviˇcova 3, 812 19 Bratislava

International Laser Centre, Ilkoviˇcova 3, 812 19 Bratislava, Slovakia

Journal of Electrical Engineering

The work investigates an increase of the density of free charge carriers in the sub-surface region of p-GaN by adding p-type dopants into the Ni-O layer of an...

Improving the ohmic properties of contacts to P–GaN by adding p–type dopants into the metallization layer

Published Online: Dec 29, 2012

Page range: 397 - 401

DOI: https://doi.org/10.2478/v10187-012-0059-x

Keywords
p-GaN, ohmic contact, contact resistivity, Au/Ni-Mg(Zn)-O/p-GaN contact structure, annealing, Auger electron spectra, secondary ion mass spectra

This content is open access.

Improving the ohmic properties of contacts to P–GaN by adding p–type dopants into the metallization layer

Published Online: Dec 29, 2012

Page range: 397 - 401

DOI: https://doi.org/10.2478/v10187-012-0059-x

Keywordsp-GaN, ohmic contact, contact resistivity, Au/Ni-Mg(Zn)-O/p-GaN contact structure, annealing, Auger electron spectra, secondary ion mass spectra

This content is open access.

Keywords
p-GaN, ohmic contact, contact resistivity, Au/Ni-Mg(Zn)-O/p-GaN contact structure, annealing, Auger electron spectra, secondary ion mass spectra