Infrared absorption of amorphous boron films containing carbon and hydrogen

Optical transmission spectra of vacuum deposited amorphous boron films are obtained, at room temperature, in the near infrared over the range 700 to 4000 cm−1 (14 to 2.5 μm). Absorption bands are observed and identified as due to hydrogen and carbon which are deliberately introduced into the films during deposition. The concentrations of hydrogen and carbon present in each film are determined by secondary-ion mass-spectrometry analysis. Intensities of IR bands attributed to hydrogen and carbon are found to correlate with hydrogen and carbon content, respectively.