Silicon-Integrated Hybrid-Cavity 850-nm VCSELs by Adhesive Bonding: Impact of Bonding Interface Thickness on Laser Performance

Abstract

Abstract-The impact of bonding interface thickness on the performance of 850-nm silicon-integrated hybrid-cavity verticalcavity surface-emitting lasers (HC-VCSELs) is investigated. The HC-VCSEL is constructed by attaching a III-V "half-VCSEL" to a dielectric distributed Bragg reflector on a Si substrate using ultrathin divinylsiloxane-bis-benzocyclobutene (DVS-BCB) adhesive bonding. The thickness of the bonding interface, defined by the DVS-BCB layer together with a thin SiO 2 layer on the "half-VCSEL," can be used to tailor the performance, for e.g., maximum output power or modulation speed at a certain temperature, or temperature-stable performance. Here, we demonstrate an optical output power of 2.3 and 0.9 mW, a modulation bandwidth of 10.0 and 6.4 GHz, and error-free data transmission up to 25 and 10 Gb/s at an ambient temperature of 25 and 85°C, respectively. The thermal impedance is found to be unaffected by the bonding interface thickness.

Novel Light Source Integration Approaches for Silicon Photonics

“…These HC‐VCSELs had an output power of 1.6 mW at 845 nm and were capable of 20 Gb/s error‐free data transmission under direct current modulation . The bonding interface is found to be of high importance for the optimization of the laser performance . By choosing the thickness of the bonding interface one can either achieve minimum threshold current, maximum output power and maximum bandwidth at a specific ambient temperature or a temperature‐stable threshold current and bandwidth.…”

Vertical‐Cavity Silicon‐Integrated Laser with In‐Plane Waveguide Emission at 850 nm

“…The top half‐structure is a GaAs‐based half‐VCSEL identical to the one used in Ref. [], consisting of a top p‐doped DBR with 23 mirror pairs, a 1‐λ‐thick separate confinement heterostructure (SCH) containing five 4‐nm‐thick quantum wells, and a 1‐λ‐thick n‐doped current spreading layer (CSL). A 30‐nm‐thick layer of is included in the DBR mirror pair closest to the SCH, for the formation of an oxide aperture via selective oxidation.…”

“…The bottom‐half structure is a SiN‐waveguide/dielectric‐DBR combination on a Si substrate consisting of a weak diffraction grating etched in an intra‐cavity SiN waveguide placed on top of a CMOS‐compatible 20‐pair / dielectric bottom DBR identical to the one used in Ref. []. The top and bottom cladding layers prevent the waveguide mode to leak into the high index GaAs half‐VCSEL and the high index dielectric DBR and Si substrate.…”

Вертикально-излучающие лазеры спектрального диапазона 1.55 mum, сформированные методом спекания

“…Частота эффективной модуляции лазеров достигает 9 GHz, ограничена низкой паразитной частотой отсечки и саморазогревом. Длинноволновые вертикально-излучающие лазеры (ВИЛ) представ-ляют интерес для реализации оптической передачи данных не только на дальние дистанции, но и на сверхкороткие расстояния (в пределе для гибридной интеграции с кремниевыми оптическими и электрон-ными схемами) [1]. По сравнению с ВИЛ ближнего ИК-диапазона ВИЛ спектрального диапазона 1.55 µm демонстрируют более низкую потребляемую мощность и меньшие оптические потери в кремниевом оптоволокне волноводах.…”