Effect of oxygen pressure on magnesium oxide dielectrics grown on GaN by plasma assisted gas source molecular beam epitaxy

A. H. Onstine, B. P. Gila, J. Kim, D. Stodilka, K. Allums, C. R. Abernathy, F. Ren, S. J. Pearton

Research output: Contribution to journalConference article

Abstract

The effect of oxygen pressure on MgO grown by RF plasma assisted gas-source molecular beam epitaxy was investigated. Increasing oxygen pressure was found to decrease the growth rate, improve the morphology and reduce the Mg/O ratio to near that obtained from bulk single crystal MgO. By contrast, the electrical characteristics of MgO/GaN diodes showed continual improvement in breakdown field and interface state density as the pressure was decreased. The lowest pressure tested, 1×10-5Torr, produced the lowest Dit, 3×1011 eV-1 cm-2, and the highest VBD, 4.4 MV/cm. Cross sectional transmission electron microscopy of the MgO grown at the lowest pressure showed the initial 40 monolayers to be epitaxial, with the remainder of the layer appearing to be fine grained poly-crystal. Comparisons with films grown using an electron cyclotron resonance (ECR) plasma suggest that higher ion energies are desirable for obtaining the best electrical characteristics.

Original languageEnglish
Pages (from-to)285-290
Number of pages6
JournalMaterials Research Society Symposium - Proceedings
Volume743
DOIs
Publication statusPublished - 2002
Externally publishedYes
EventGan and Related Alloys - 2002 - Boston, MA, United States
Duration: 2002 Dec 22002 Dec 6

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Effect of oxygen pressure on magnesium oxide dielectrics grown on GaN by plasma assisted gas source molecular beam epitaxy'. Together they form a unique fingerprint.

  • Cite this