[Research on the resistivity of the HFCVD diamond films]

Resistivity of the diamond films by HFCVD technology is analyzed and studied. The I-V curve of the film is depicted in vertical direction using electrode of aluminum film plated on the surface of the diamond films. Further the resistivity of the films is determined. The following conclusion is derived on the basis of the analysis of Raman, SEM and XRD. The resistivity of the diamond films is in relation to the size of the grains and grain orientation of the surface of the films. The larger in average the grain of the films has, the greater the resistivity of the films is. Besides, the film with grain orientation of (110) has a larger resistivity. In addition, the fewer the defect and impurity of the film has, the larger the resistivity of the films is. Therefore, it is important to add the grain size of the film in average, and to increase the grain orientation rate of (110)/(111) in order to gain diamond films that have larger resistivity and good property of insulation. To reduce the content of structure defect and impurity is also an effect way to raise the resistivity of the films.