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

• Published in: Physica status solidi. A, Applications and materials science Vol. 207; no. 9; pp. 2023 - 2028
• Main Authors: Araújo, D., Bustarret, E., Tajani, A., Achatz, P., Gutiérrez, M., García, A. J., Villar, M. P.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Berlin WILEY-VCH Verlag 01-09-2010; WILEY‐VCH Verlag; Wiley-VCH; Wiley
• Subjects: Chemical and Process Engineering; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; diamond; dislocations; Engineering Sciences; Exact sciences and technology; homoepitaxy; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; transmission electron microscopy; CVD; Homoepitaxy; Epitaxial layers; Transmission electron microscopy; Crystal orientation; Mismatch lattice; Diamonds; Surface preparation; Cleavage; Polishing; Focused ion beam technology; Dislocations
• ISSN: 1862-6300; 1862-6319
• DOI: 10.1002/pssa.201000141

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.