Fabrication of high-aspect-ratio Fresnel zone plates by e-beam lithography and electroplating.
The fabrication of gold Fresnel zone plates, by a combination of e-beam lithography and electrodeposition, with a 30 nm outermost zone width and a 450 nm-thick structure is described. The e-beam lithography process was implemented with a careful evaluation of applied dosage, tests of different bake-out temperatures and durations for the photoresist, and the use of a developer without methylisobutylketone. Electrodeposition with a pulsed current mode and with a specially designed apparatus produced the desired high-aspect-ratio nanostructures. The fabricated zone plates were examined by electron microscopy and their performances were assessed using a transmission X-ray microscope. The results specifically demonstrated an image resolution of 40 nm.
Chen
Y T
YT
Institute of Physics, Academia Sinica, Taipei 115, Taiwan.
Lo
T N
TN
Chiu
C W
CW
Wang
J Y
JY
Wang
C L
CL
Liu
C J
CJ
Wu
S R
SR
Jeng
S T
ST
Yang
C C
CC
Shiue
J
J
Chen
C H
CH
Hwu
Y
Y
Yin
G C
GC
Lin
H M
HM
Je
J H
JH
Margaritondo
G
G