Sensors and Electron Devices Directorate Research Areas

Growth and Analysis of Organometallic Vapor Phase Epitaxial III-Nitride Device Structures

Advisor: Jones, Kenneth A. (ken.a.jones@us.army.mil 301.394.2005)
Adelphi, MD

Key words: Organometallic vapor phase expitaxy, III-Nitrides, GaN/AlGaN devices, GaN substrates, Ion implant activation

Device structures that require thin layers with abrupt junctions are usually grown by organometallic vapor phase epitaxy (OMVPE) or molecular beam epitaxy. Although OMVPE is more cost effective and more amenable to selective area epitaxy, its growth is more complex because it involves surface chemical reactions and its layers are often less uniform. We are currently growing the III-nitrides with application to GaN/AlGaN high power and RF devices and encapsulates for ion implanted GaN and SiC devices. Pendeo-epitaxial device structures are grown to measure the effects of defects on device properties by comparing the device characteristics of devices  fabricated from pendeo-materials with those fabricated from material grown in the usual way. To improve the quality of device structures, we are analyzing the grown structures with double crystal x-ray diffraction, Rutherford backscattering spectroscopy, transmission electron microscopy, secondary ion mass spectroscopy, transmission electron microscopy, secondary ion mass spectroscopy, scanning Auger spectroscopy, scanning electron microscopy, and photoluminescence and photoreflection spectroscopy. These results are correlated with the electrical Hall, CV, and deep-level transient spectroscopy measurements and the device characteristics.