An Innovative Cell Microincubator for Drug Discovery Based on 3D Silicon Structures

Figure 8

Interferometric signal, digitally filtered and normalized with respect to the peak value, collected on an as-fabricated 8 μm 3D-SMS (empty gaps before cell culture). We performed also a Hilbert transform to obtain the envelope of the signal. : optical path-length of the empty gap (only air is inside the gaps) that is obtained as the distance between the 2nd and 3rd peak (as well as between the 4th and 5th peak) of the envelope of the interferometric signal. : optical path-length of the silicon wall that is obtained as the distance in optical path-length between the 1st and 2nd peak (as well as between the 3rd and 4th peak) of the envelope of the interferometric signal.