Nanophotonic integrated active-passive InP membrane devices and circuits fabricated using ArF scanner lithography

Abstract

We present a novel fabrication approach to an integrated nanophotonic platform, based on a III-V membrane bonded to a Si substrate with benzocyclobutene (BCB). The process incorporates a hybrid lithography strategy combining deep-UV and electron-beam lithography on the same wafer. We report for the first time the usage of deep-UV scanner lithography for the fabrication of the active-passive tapers and sub-micron waveguides on the same wafer, which enables better critical dimension control, uniformity, and reproducibility. The platform uses an active-passive butt-joint interface and includes components such as distributed feedback (DFB) and distributed Bragg reflector (DBR) lasers, electro-optical (EO) and electro-absorption (EA) modulators, and sub-micron ultra-confined passive waveguides, all monolithically integrated into a single membrane layer. The active devices have a heat sink achieved by ultra-thin BCB bonding. Lasers demonstrate up to 26 mW of optical power in the waveguide and a direct modulation bandwidth of up to 21 GHz. The modulators show static extinction up to 28.8 dB.