Nonhydrogen germanium carbide (GexC[Formula: see text]) films were prepared by KrF pulsed lasers deposition (PLD), and the effects of different germanium contents on the microstructures, optical properties and adhesion properties of the GexC[Formula: see text] films were studied. XRD measurements showed that the GexC[Formula: see text] films with different germanium contents were of amorphous structure. XPS analysis showed that the C/Ge atomic ratios of GexC[Formula: see text] films were close to those of corresponding targets. The intensity of Ge3[Formula: see text] peak in the GexC[Formula: see text] films increased and the intensity of C1s peak decreased with the increase of the germanium content. The GexC[Formula: see text] films’ [Formula: see text]C bond contents increased from 46.4% to 69.7%. Ellipsometry and infrared transmission spectral measurements showed that the refractive index of GexC[Formula: see text] films increased from 2.5 to 3.5 at the wavelength of 1[Formula: see text][Formula: see text]m with the increase of germanium content. The extinction coefficient of GexC[Formula: see text] film was of the order of 10[Formula: see text] in the infrared band when the germanium content was less than 10[Formula: see text]at.%. The adhesion tests showed that the adhesion performances of GexC[Formula: see text] films were better when the germanium content increased.
First principles investigation of high thermal conductivity in hexagonal germanium carbide(2H-GeC)
