Micro-transfer-printed narrow-linewidth III-V-on-Si double laser structure with a combined 110 nm tuning range.

In this work, we demonstrate for the first time a narrow-linewidth III-V-on-Si double laser structure with more than a 110 nm wavelength tuning range realized using micro-transfer printing (µTP) technology. Two types of pre-fabricated III-V semiconductor optical amplifiers (SOAs) with a photoluminescence (PL) peak around 1500 nm and 1550 nm are micro-transfer printed on two silicon laser cavities. The laser cavities are fabricated in imec's silicon photonics (SiPh) pilot line on 200 mm silicon-on-insulator (SOI) wafers with a 400 nm thick silicon device layer. By combining the outputs of the two laser cavities on chip, wavelength tunability over S+C+L-bands is achieved.

High-alignment-accuracy transfer printing of passive silicon waveguide structures.

We demonstrate the transfer printing of passive silicon devices on a silicon-on-insulator target waveguide wafer. Adiabatic taper structures and directional coupler structures were designed for 1310 nm and 1600 nm wavelength coupling tolerant for ± 1 µm misalignment. The release of silicon devices from the silicon substrate was realized by underetching the buried oxide layer while protecting the back-end stack. Devices were successfully picked by a PDMS stamp, by breaking the tethers that kept the silicon coupons in place on the source substrate, and printed with high alignment accuracy on a silicon photonic target wafer. Coupling losses of -1.5 +/- 0.5 dB for the adiabatic taper at 1310 nm wavelength and -0.5 +/- 0.5 dB for the directional coupler at 1600 nm wavelength are obtained.