Two different integration schemes for front-end optical receivers have been demonstrated for GaAs- and InP-based material systems. An InP-based p-i-n FET vertically integrated circuit exhibits a bandwidth greater than 2 GHz. The FET exhibits an extrinsic gm = 450 mS/mm and fT = 9 GHz. The GaAs-based planar structure consists of a modulated-barrier photodiode and a doped channel FET made with the same epitaxial layers. The detector has an optical gain of 200, and the FET performance is characterized by gm = 250 mS/mm, fT = 12 GHz, and fmax = 21 GHz.
