Comparison Of DC Bias And Pulse Bias

- Feb 10, 2018-

The traditional arc ion plating refers to the DC negative bias is applied on the substrate to control ion bombardment energy. The deposition process has the following disadvantages:  

● The high temperature rise of the substrate is not conducive to the deposition of hard films on the low-temperature tempering substrate.

● High-energy ion bombardment caused serious sputtering, and the hard thin film cannot be simply by increasing ion bombardment energy synthesis of high reaction threshold energy.

In the DC bias arc ion plating process, In order to restrain the ion constant bombard the substrate surface and caused the substrate temperature is too high, the main measure is to decrease the deposition power, shorten the deposition time, the use of intermittent deposition and other measures to reduce the deposition temperature, these measures are called "Energy Control Method". Although this method can reduce the deposition temperature, it also reduces some properties of the film, while reducing the production efficiency and the stability of the film quality. Therefore, it is difficult to popularization and application.

In the pulse bias arc ion plating process, because of the ions bombard the substrate surface with the non-continuous pulse, by adjusting the duty ratio of the pulse bias, the temperature gradient between the inner and surface of the matrix can be changed, and then the equilibrium compensation effect of the temperature between the inner and the surface of the substrate can be changed, so as to achieve the purpose of regulating the deposition temperature. In this way, the pulse height of the applied bias and the temperature of the workpiece can be separately (no influence or small influence) adjusted. High-voltage pulses are used to obtain the bombardment effect of high-energy ions to improve the microstructure and properties of the thin film, by reducing the duty ratio to decrease the total heating effect of ion bombardment to reduce the deposition temperature.