Prakt. Met. Sonderband 52 (2018) 49
3.3.1 Mechanical properties
Ki
HE Automated nanoindentation on the wafer level can be used to determine Young's modulus
ng Kul and hardness [e.g. 13]. A sufficient film thickness of about 1 um is recommended to avoid
Weyer ED substrate effects. Residual stress in thin-film systems can be determined with cantilever
XPS have‘ curvature measurements either on a wafer-level or using stress chips [16 - 17]. Using
Sen 4 cantilever array wafers, a time- and space-resolved high-throughput characterization of
Y fing 0 | stresses during sputtering and thermal processing of thin films can be performed [18].
tog N Micromachined cantilevers are an example for MEMS tools in combinatorial materials
X 8s put science [19].
ASS ang
NIS approach
les from the 3.3.2 Electrical properties
A high-throughput modular test-stand [14] has been developed which uses four-point
resistivity probes for the measurement of electrical resistance R at the predefined
measurement areas, see Figure 2b). This method is applicable for (semi)conducting thin
films. For insulating thin films impedance spectroscopy needs to be applied. Temperature-
Jeasurement dependent resistance measurements can be used to identify phase transformations in thin-
1 nStruments film libraries, see below.
1 be confined
M-{hroughput
Cal gradients 3.3.3 Optical properties
actograms is
The optical appearance of the materials libraries in each state are captured using a photo
test-stand [20]. Further optical properties can be acquired using a transmission test-stand,
comprising a light source, automated wafer positioning and an optical spectrometer, from
which e.g. optical band-gap values and optical absorption properties can be determined. By
combining optical and electrical measurements, e.g. new transparent conductive oxides
1 oy diferent could be investigated.
Case custom-
d to perform
of electrical 3.3.4 (Photo)Electrochemical properties
An optical scanning droplet cell was developed which can perform three-electrode
electrochemical measurements on the materials library level und with and without
illumination at different wavelengths [21]. The photocurrent is taken as a descriptor for the
characterization of (photo)electro-catalyst materials [e.g. 22 - 23].
3.3.5 Magnetic properties
Magnetic properties of thin-film materials libraries can be assessed by using a magneto-
optical Kerr effect (MOKE) set-up. However, this method is limited to gain information on the
shape of the hysteresis loop and the coercive field. This is sufficient to identify ferromagnetic
regions on materials libraries and their soft or hard magnetic properties [e.g. 24 - 27]. For
the high-throughput measurement of the magnetization up to now no high-throughput
method exists.
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yp tnt
