The concentration gradient of boron along the growth direction in boron doped chemical vapor deposited diamond

The boron concentration in the growth direction of hot filament chemical vapor deposited boron doped diamond film is studied. Raman spectroscopy showed that the asymmetry of 1332 cm−1 peak was enhanced in the growth direction. The estimated boron content from the position of the Lorentzian contribution to the 500 cm−1 Raman feature and the electron probe microanalysis on the cross-section of the diamond film reveal a monotonically increasing of boron concentration in the film growth direction.