Up to 9Gbit/s data transmission with monolithically integrated VCSELs and PIN photodiodes

Up to 9Gbit/s data transmission with monolithically integrated VCSELs and PIN photodiodes is reported. The complete layer structure of the monolithic transceiver chip is grown in one epitaxial run using molecular beam epitaxy on GaAs substrate. The layers of the PIN PD on top of the VCSEL structure are selectively removed by several wet and reactive-ion etching processes. The top-emitting, transverse multimode oxide-confined VCSEL is separated by a 2 to 4 μm wide trench from the PIN PD. The 3 μm thick anti-reflection coated PD shows responsivities of 0.61 A/W at 850 nm, which corresponds to a quantum efficiency of nearly 88%. Digital data transmission experiments were performed in back-to-back (BTB) mode in order to avoid dispersion effects of the glass fiber.