Homogeneity Control Of Magnetron Sputtering Using Circular Target And Its Effect On The Quality Of Deposited Film

In this paper, copper plating using magnetron sputtering with circular target is employed to study the effects of excitation current on the etching trace of magnetron target, and the effects of excitation current and the distance between target and substrate on the distribution uniformity of the coating layer. According these data, one program-controlled excitation power is designed. Through controlling the waveshape of the excitation current in the coil, the aim to improve the utilization of the target is completed, on the premise of ensuring the accuracy of the subject coating.The structure and morphology of the magnetron sputtering depositing layer are analyzed by X-ray diffraction and scanning electron microscopy, respectively; Nano-indentation, Nano Indenter XP type, is used to measure the film thickness; and the contour morphology of etching trace in the magnetron target is tested by profile meter. VC++ is employed to program.The results show that: the cross section depth of the etching trace shows linear relationship with sputtering time and excitation current; the cross section width of the etching trace can be regarded as a constant which is not affected by sputtering time or excitation current, but just decided by the structure of the magnetic field. The central position of the etching trace enlarges with the increase of the excitation current. According to the results above, it is found that the morphology of the etching ring shows Gaussian function form; three types of non-steady excitation current are designed to study the target utilization, the results show that the target utilization is improved under all the three types of excitation current.According to the results above, the controlling power circuit of excitation current is designed, which is directly controled by computer through D/A card and is amplified by V-channel field-effect transistor. After the output of the D/A converted signals, they are directly amplified and introduced into the coil by the calibration of the digital potentiometer scale. Through defining initial value, step value, time interval and processing time four parameters of controlling program, the waveshape of excitation current can be realized.