The influence of substrate properties on optoelectronic integrated circuits

The electrical and chemical properties of semi-insulating GaAs substrates play a significant role in the behavior of high speed optoelectronic integrated circuits. The uniformity of the threshold voltage across a wafer, along an ingot, and between different ingots are the main concerns which determine the successful operation of these circuits. The purity of the grown ingot, the quality of the ingot anneal, the perfection of the crystal near the surface, and the trap distributions are the major influences of the substrate on the finished devices.