Comparison of the crystalline quality of homoepitaxially grown CVD diamond layer on cleaved and polished substrates

✍ Scribed by Araújo, D. ;Bustarret, E. ;Tajani, A. ;Achatz, P. ;Gutiérrez, M. ;García, A. J. ;Villar, M. P.

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 686 KB
• Volume: 207
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.201000141

✦ Synopsis

Abstract

A transmission electron microscopy (TEM) study, comparing homoepitaxial diamond layers grown on different substrate surface preparation states and crystallographic orientation is presented. Quality of epilayers grown on {111} cleaved surface and on {001} polished one is evaluated in terms of crystalline defects. Focused ion beam (FIB‐dual beam) sample preparations are observed by TEM using the {111}, {400} and {022} reflections of the [011] pole. Burgers vector analysis allowed to conclude the presence of 60° dislocations oriented along all the different 〈110〉 directions in the cleaved sample, while no dislocations are observed on the polished one. A complete dislocation analysis is performed for that sample. The presence of dislocations in an undoped (i.e. fully lattice matched) epilayer is surprising; and is probably induced by atomic steps, generated by the cleavage process. This notes down the importance of the substrate if high quality diamond epilayers want to be grown.