TY  - JOUR
U1  - Zeitschriftenartikel, wissenschaftlich - begutachtet (reviewed)
A1  - Ellingen, Elias
A1  - Rohde, Markus
A1  - Stahl, Bastian
A1  - Lange, Robert
T1  - Fourier scatterometry for compensation of tilt and curvature deviations of two-photon polymerization three-dimensional printers
JF  - Journal of Optical Microsystems
N2  - A Fourier scatterometry setup is evaluated to recover the key parameters of optical phase gratings. Based on these parameters, systematic errors in the printing process of two-photon polymerization (TPP) gray-scale lithography three-dimensional printers can be compensated, namely tilt and curvature deviations. The proposed setup is significantly cheaper than a confocal microscope, which is usually used to determine calibration parameters for compensation of the TPP printing process. The grating parameters recovered this way are compared to those obtained with a confocal microscope. A clear correlation between confocal and scatterometric measurements is first shown for structures containing either tilt or curvature. The correlation is also shown for structures containing a mixture of tilt and curvature errors (squared Pearson coefficient r2 = 0.92). This compensation method is demonstrated on a TPP printer: a diffractive optical element printed with correction parameters obtained from Fourier scatterometry shows a significant reduction in noise as compared to the uncompensated system. This verifies the successful reduction of tilt and curvature errors. Further improvements of the method are proposed, which may enable the measurements to become more precise than confocal measurements in the future, since scatterometry is not affected by the diffraction limit.
KW  - Fourier scatterometry
KW  - grating reconstruction
KW  - transmission phase gratings
KW  - two-photon polymerization
UN  - https://nbn-resolving.org/urn:nbn:de:hbz:1044-opus-76295
SN  - 2708-5260
SS  - 2708-5260
U6  - https://doi.org/10.1117/1.JOM.3.4.043501
DO  - https://doi.org/10.1117/1.JOM.3.4.043501
VL  - 3
IS  - 4
SP  - 12
S1  - 12
PB  - SPIE
ER  -