Airbridged high-speed AlGaAs-GaAs ridge waveguide lasers

The design of a high modulation response multiple-quantum-well ridge waveguide laser in AlGaAs-GaAs, with low parasitics is discussed. The device was fabricated on a semi-insulating substrate with a wide top contact, and airbridges have been used to connect the ridge top contact to the bonding pads on the semi-insulating substrate. The 3-dB frequency response of the laser has been measured to be 21 GHz, which is a record for unstrained quantum-well AlGaAs-GaAs lasers.