In silicon photonics low surface roughness and excellent uniformity are achieved by state-of-the-art 193 nm optical lithography
[1]. Recently we demonstrated low-excess-loss arrayed waveguide grating on a microphotonic InP platform [2]. We
expect that the same methods will have a high impact on InP nanophotonics, where so far the losses have been limited to
2.5 dB/cm [3]. Silicon-on-insulator (SOI) waveguides with comparable dimensions and mode confinement typically achieve
1.5 dB/cm [4]. In this work for the first time we evaluate the use of 193 nm scanner lithography for InP nanofabrication by
fabricating a test-cell for propagation loss analysis in the IMOS platform [5]. A record low propagation loss of 1.3±0.1 dB/cm
is demonstrated in a Mach-Zehnder interferometer (MZI) circuit and a microring resonator Q-factor up to 62.000 with 4 nm
FSR is measured.