Structure of unepitaxial crystallites in a homoepitaxial diamond film

Unepitaxial crystallites (UC, non-epitaxial crystallites) were spontaneousl y grown in a homoepitaxial diamond film deposited by chemical vapor deposit ion (CVD) method at a high growth rate. Degradation of electrical and optic al properties of the deposited films was attributed to the growth of the UC . In order to investigate the structure of the UC, electron microscopic ana lysis was performed on the UC. Focused ion beam thinning (FIB), a field emi ssion scanning electron microscopy (FESEM) and a high-resolution transition electron microscopy (HRTEM) were employed for the investigation. Dislocati ons were observed in the growth region in the < 001 > direction. Nanometer- sized grains were observed in the growth region in the < 111 > direction. M ost of the grains rotated by 70.53 degrees around the < 110 > axis, corresp onding to Sigma3 coincidence site lattice (CSL) relation. Tbe (111) Sigma3 grain boundary was dominant in number and was extremely long in length. Inc oherent Sigma3 boundaries connected to the {111} Sigma3 boundary were much shorter. (C) 2001 Elsevier Science B.V. All rights reserved.