title: Flip-chip integration of tilted VCSELs onto a silicon photonic integrated circuit.
abstract: In this article we describe a cost-effective approach for hybrid laser integration, in which vertical cavity surface emitting lasers (VCSELs) are passively-aligned and flip-chip bonded to a Si photonic integrated circuit (PIC), with a tilt-angle optimized for optical-insertion into standard grating-couplers. A tilt-angle of 10° is achieved by controlling the reflow of the solder ball deposition used for the electrical-contacting and mechanical-bonding of the VCSEL to the PIC. After flip-chip integration, the VCSEL-to-PIC insertion loss is -11.8 dB, indicating an excess coupling penalty of -5.9 dB, compared to Fibre-to-PIC coupling. Finite difference time domain simulations indicate that the penalty arises from the relatively poor match between the VCSEL mode and the grating-coupler.
authors.forename: Huihui
authors.initials: H
authors.lastname: Lu
authors.forename: Jun Su
authors.initials: JS
authors.lastname: Lee
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
authors.forename: Carmelo
authors.initials: C
authors.lastname: Scarcella
authors.forename: Paolo
authors.initials: P
authors.lastname: Cardile
authors.forename: Aidan
authors.initials: A
authors.lastname: Daly
authors.forename: Markus
authors.initials: M
authors.lastname: Ortsiefer
authors.forename: Lee
authors.initials: L
authors.lastname: Carroll
authors.forename: Peter
authors.initials: P
authors.lastname: O'Brien