Vertically Stacked Passive Silicon Photonic Chiplet by µ-Transfer Printing

We device double-layer stacked silicon photonic MMIs by µ-Transfer Printing. A 900×100-µm
²
-size chiplet consisting of a 220/60-nm-thick silicon core/slab structure is transferred twice onto thermal- and TEOS-SiO
2
under-cladding layers.