By Topic

Measurement of induced surface charges, contact potentials, and surface states in GaN by electric force microscopy

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $31
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

4 Author(s)
Bridger, P.M. ; Thomas J. Watson, Sr. Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125 ; Bandic, Z.Z. ; Piquette, E.C. ; McGill, T.C.

Your organization might have access to this article on the publisher's site. To check, click on this link: 

We have studied molecular beam epitaxy grown GaN films of both polarities using electric force microscopy to detect sub 1 μm regions of charge density variations associated with GaN extended defects. The large piezoelectric coefficients of GaN together with strain introduced by crystalline imperfections produce variations in piezoelectrically induced electric fields around these defects. The consequent spatial rearrangement of charges can be detected by electrostatic force microscopy and was found to be on the order of the characteristic Debye length for GaN at our dopant concentration. The electric force microscope signal was also found to be a linear function of the contact potential between the metal coating on the tip and GaN. Electrostatic analysis yielded a surface state density of 9.4±0.5×1010cm-2 at an energy of 30 mV above the valence band indicating that the GaN surface is unpinned in this case. © 1999 American Institute of Physics.

Published in:

Applied Physics Letters  (Volume:74 ,  Issue: 23 )