TY  - JOUR
ID  - APLStrasser:07
T1  - Sidewall roughness measurement inside photonic crystal holes by atomic force microscopy
A1  - Strasser, Patric
A1  - Robin, Franck
A1  - Carlström, C. F.
A1  - Wüest, Robert
A1  - Kappeler, Roman
A1  - Jäckel, Heinz
JA  - Nanotechnology
Y1  - 2007
VL  - 18
IS  - 40
SP  - 405703
SN  - 0957-4484
N2  - We present a measurement technique to quantify sidewall roughness inside planar photonic crystal (PhC) holes. Atomic force microscopy is used to scan hole cross-section profiles. By fitting a circle onto each scan line and subtracting this circle from the measurement data,a quantitative value for the deviation from the ideal cylindrical holeshape is extracted. We investigate the sidewall roughness of InP-basedPhC holes depending on the nitrogen content of the semiconductor etching plasma. The existence of a trade-off between hole undercut andsurface roughness by optimizing the flux of nitrogen during the plasmaetching of the PhC holes is confirmed. We further quantify with this technique the influence of the direct-writing of octagons instead of circles by electron-beam lithography on the measured roughness.
ER  -