Method for replacing chlorine atoms on a film layer

A method for replacing chlorine atoms on a film layer comprising the steps of:

• placing a carrier having the film layer into a chamber, the film layer having a plurality of chlorine atoms on a surface thereof, wherein the film layer comprises a metal layer, a semiconductor layer and an insulative layer;
• passing a first gas and a second gas into the chamber to form a gas mixture, a volume ratio of the second gas being less than one-tenth of the volume ratio of the first gas, wherein the first gas is an oxygen gas, and an electronegativity of an ion formed by dissociating the second gas is greater than an electronegativity of a chloride ion;
• dissociating the gas mixture by a plasma process to form an ionic mixture, wherein a power condition of the plasma process is 1250 watt to 1750 watt, a pressure condition of the plasma process is 60 mTorr (milliTorr) to 100 mTorr, and a processing time of the plasma process is 10 sec to 15 sec;
• and
• bombarding the ionic mixture onto a surface of the film layer, causing the chlorine atoms through a reaction to be replaced by one type of ions of the ionic mixture.