The samples used for the parameter studies were cut to the desired shape using a scalpel, and peeled of the wafer to be transfer onto a custom stretching setup. The setup consisted of two micrometer screw drive actuated slides fixed onto a plexiglass base plate, aligned and facing each other. The sample to be stretched was immobilized on both ends onto each of the slides. By rotating either (or both) of the screws, the space between the slides could be modulated, effectively stretching the sample. The whole assembly was placed under a microscope (Keyence VHX-7000 series) for image acquisition.