Statistical process development and optimization of gallium arsenide MESFET-MSM optoelectronic integrated circuits

In the last ten years, the emergence of optoelectronic technology has revolutionized the communications industry. Unfortunately, this technology is expensive and is thus only affordable to major telecommunication carriers, that is, phone companies. To further expand the applications of optoelectronic technology from "long-haul" communication to short-distance optical interconnects, the development of cost-effective devices for high performance computing and communication applications is urgently needed.;OptoElectronic Integrated Circuits (OEIC) composed of photodetectors and lasers on the same substrate with transistors promise several advantages over their hybrid counterparts; among these are enhanced performance and low cost. To address the problems or barriers which integration technology faces, the Gallium-Arsenide (GaAs) Metal-Semiconductor Field Effect Transistor (MESFET) and Metal-Semiconductor-Metal (MSM) technology provide a reasonable way for achieving this end. The MSM photodetector structure, which consists of a set of interdigitated metal fingers, is notably compatible with the MESFET process making monolithic integration possible.;The focus of this thesis work is on the process development and optimization of GaAs MESFET-MSM based integrated circuits using a statistical experimental design technique. This technique provides an efficient and reliable way for both developing a new process and optimizing an existing one, when a large number of process variables are involved. Statistically significant transfer characteristics of key process modules in this GaAs MESFET-MSM process are obtained and used for process optimization. The optimal process is obtained by both maximizing the device and circuit performance and minimizing the transmitted variations from the process to the finished circuits. Therefore, a robust process is achieved in the sense that the process variations are least transmitted to the finished product.