EML Based on Identical Epitaxial Layer, Side-Wall Grating and HSQ Planarization

Abstract

We present an electroabsorption modulated laser based on an identical epitaxial scheme, side-wall grating, on-chip microwave probe interface, and a new low-permittivity planarization method. The modulation speed is significantly increased by reducing the electrode capacitance by planarizing with a 5-µm-thick HSQ layer. Furthermore, implementing the electrode with a direct ground-signal-ground probe interface provides a straightforward interconnection that obviates the need for an external circuit and bonding wires. The device operates at 1565 nm wavelength with stable single-mode lasing, no modehopping, and a side mode suppression ratio above 35 dB. An extinction ratio of 19.5 dB was recorded at the maximum modulator bias of −4 V. The electrical to optical power response of the modulated signal at -3-dBo demonstrated a 19 GHz bandwidth at an extinction ratio of 7 dB, which supports error-free data transmission up to 27 Gbit/s.

AlGaInAs/InP EML with Sidewall Grating Distributed Feedback Laser and Quantum Well Intermixing Technology

“…2(f) shows the maximum ER is reduced to 27 dB for L D =0.45 nm when the length of the EAM is decreased from 150 μm to 100 μm. The simulated electrical to optical (E/O) frequency response for a 150 μm EAM and the comparable measured result from [5] at −1.6 V bias voltage are shown in Fig. 2(g), with a good agreement of a 17 GHz −3-dB bandwidth.…”