Combined atomic force microscopy and scanning tunneling microscopy imaging of cross-sectioned GaN light-emitting diodes.
Cross-sectional scanning tunneling microscopy (STM) was combined with atomic force microscopy (AFM) over the same area to characterize a cross-sectioned GaN light emitting diode. Because GaN is typically grown on a non-native substrate and also forms a wurtzite crystal structure, a cryogenic cleaving technique was developed to generate smooth surfaces. The depletion region surrounding the p-n junction was clearly identified using STM. Furthermore, by imaging under multiple sample biases, distinctions between the n-doped and p-doped GaN could be made.
Bender
J W
JW
North Carolina State University, Analytical Instrumentation Facility, Raleigh, North Carolina, USA. benderjw@engr.sc.edu
Salmon
M E
ME
Russell
P E
PE