Interface Engineering and Defect Control in Heteroepitaxial Growth of GaN
Abstract
The technique of photo electron emission microscopy (PEEM) combined with UV free electron laser (UV-FEL) excitation has been employed for in situ studies of the dynamics of semiconductor interfaces. Wide bandgap semiconductors such as diamond, GaN and AlN exhibit a small or even negative electron affinity. The PEEM results show a shift of the photo threshold or in situ annealed diamond surfaces consistent with an increase in the electron affinity due to the desorption of hydrogen. The electron emission from an array of GaN emitters has been observed with PEEM and field emission electron microscopy (FEEM). Both measurements indicate nearly uniform emission from all of the elements of the array. The technique of PEEM with UV-FEL has been applied to explore a buried interface. The results display a buried Ti contact below an AlN layer. The dynamics of the formation of nanometer epitaxial islands on Si has been shown with PEEM. A unique aspect is that both ripening and coalescence processes are observed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1998
- Accession Number
- ADA353355
Entities
People
- Harald Ade
- Robert F Davis
- Robert J. Nemanich
Organizations
- North Carolina State University