Far-UV photoluminescence of boron-doped diamond: Cross interaction between boron and diamond

Photoluminescence (PL) spectra of boron-doped diamonds (BDD) were recorded with far-ultraviolet excitation. Upon 175 nm excitation, emissions of two types were observed; a broad emission band A, was recorded about 560 nm, whereas three distinct PL lines were detected at 194.0, 231.5 and 281.0 nm for the first time. The photoluminescence excitation spectra (PLE) of BDD were measured also on monitoring PL lines at 281 and 560 nm; their PLE spectra appear dissimilar. Compared to the absorption spectrum of CVD diamond, we conclude that the energy absorbed by the host diamond became transferred to the dopant boron atom, which subsequently radiated emission band A. According to the emission spectra of atomic boron from photolysis at 180 nm of diborane(6) dispersed in solid neon at 4 K, the PL lines at 194.0, 231.5 and 281.0 nm are due to electronic transitions of boron atoms in the BDD lattice.