Monolithic integration of GaAs/AlGaAs double-heterostructure LED's and Si MOSFET's

Fully monolithic integration of interconnected GaAs/Al-GaAs double-heterostructure LED's and Si MOSFET's is demonstrated for the first time. The Si MOSFET's, with a gate length of 5 µm and gate width of 1.6 mm, have almost the same characteristics as those of control devices fabricated on a separate Si wafer. The LED output collected by a microscope lens with a numerical aperture of 0.65 is about 6.5 µW at 100- mA dc current. LED modulation rates up to 27 Mbit/s have been achieved by applying a stream of voltage pulses to the MOSFET gate. The modulation rate is limited by the speed of the MOSFET.