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(a) Defect location 1
(c) Defect location 2
(b) Defect location 2
(a) Defect locations on SLM 2
Figure 5.10 : (a) Locations of defects on SLM 2 observed under the microscope
(see lines sketched on mask), (b) An 32×32 image of the modulation depth of the
pixels on SLM 2, overlaid with sketches of defects in (a). At 0.37 THz, the SLM
provides around 20% amplitude modulation at the darker regions on the image, and
has zero modulation at the brighter regions. The defects cut off some SLM pixels
from their Schottky pads, thus the SLM cannot provide any amplitude modulation
at the corresponding pixel locations.
Figure 5.9 : Microscope images of defect locations on SLM 1 indicated on Fig-
ure 5.8(a). Location 1 has a crack whereas location 2 and 3 have fabrication defects.
(b) Modulation depth image of SLM 2