An integrated 155 Mbps digital transmitter using a 1.3 /spl mu/m wavelength thin film LED

摘要

This paper reports, for the first time, InP-based thin film surface emitters bonded directly to digital silicon CMOS circuits operating at 155Mbps with digital I/O for application in a three dimensional, through-silicon, communication system. The digital CMOS driver circuitry consisted of a 2-stage tapered buffer, a current switch, and a constant bias current source. The current switch was used before the power transistor stage to avoid voltage spikes. The output stage included a current source to DC bias the LED for increased speed. Careful layout design of the power transistors was performed to minimize any series resistance and to improve the current carrying capability.