Chapter 1 – Epitaxial Film Growth and Characterization

Publisher Summary Over the past few years, the market for compound semiconductor-based devices has continued to expand and mature, and much of the commercial promise for these materials is realized. Many devices have now reached the stage of significant manufacturing volumes, including light-emitting diodes, laser diodes, solar cells, and electronic devices, such as high electron mobility transistors and heterojunction bipolar transistors. All of these devices require the deposition of thin epitaxial layers, and these layers often have lower defect and impurity levels as compared to bulk materials. This chapter focuses on epitaxial film growth and its characterization. The deposition of these epitaxial layers could be performed through various deposition techniques such as vapor phase epitaxy, liquid phase epitaxy, molecular beam epitaxy (MBE), and metal-organic chemical vapor deposition (MOCVD). Of these, MBE and MOCVD are dominant because they are capable of reproducibly generating the advanced device structures that require very thin layers and monolayer abrupt transitions in composition. The MBE has tended to dominate the growth of electronic devices where volumes are relatively low and a premium is placed on interface control. The MOCVD has tended to dominate the growth of optoelectronics devices where cost is more important and high capacity tools are required. High throughput production has raised a new challenge for whole wafer and nondestructive material characterization that is quite different from traditional single point and destructive measurements. In a production environment, the necessity of reliable and rapid turnaround completely nondestructive wafer mapping characterization, techniques have become apparent and are currently being developed.