Plasma Parameter Diagnosis On Arc Ion Plating By Langmuir Probe

Arc ion plating is a good thin film deposition technology,Compared with the form of other film coating,it has unparalleled advantages such as the high ionization rate,high deposition rate and good strength of the membrane-binding and so on,prepared to use this technology nitride films,such as TiN,CrN,has been widely used.at the industrial production.Arc ion plating plasma properties has a decisive effect on the quality of thin film deposition,testing its parameters are the basis for the necessary research work.However,It is reported about little specific data.The main reason is the lack of a diagnosis of arc ion plating plasma effective means by far.Specifically,when using the Langmuir probe diagnosis on the arc ion plating plasma,it encounters the problems such as high electron current density,strong disturbance and pollution prone.The Langmuir double probe system based on Virtual Instrument was used to diagnose arc ion plating plasmas.Using of the double probe restrained the probe current no more than the ion saturation limit,so that protected the probe from being destroyed in high-density arc ion plating plasmas by collection of electronic current.Virtual Instrument can choose the data sample rating and sample average with large number according to the plasma disturbance frequency.The discrete Fourier Transform(DFT) smoothing method was used to overcome the strong fluctuations inherently exist in the arc ion plating plasmas.The design of the probe tip avoids the deposition caused electric short between the tip and the supporter.Methods mentioned above make it a real that the probe can work stably for a long time,and it satisfy the practical requirement.The probe diagnosis is carried out based on the real arc ion plating process parameters.The results showed that the plasma density of the regional workpiece increased with increasing arc current and gas pressure,while the electron temperature changed little with the current and the pressure.On the other hand,using of double-target exhibited higher plasma density and electron temperature than using of single-target.It has been also found experimentally that plasma density by dual-target discharge is more uniform than that by single-target discharge.The result provided basic parameters of the arc plating plasmas that are useful to materials coating processes.