Abstract: A trench is formed at an exposed portion of a semiconductor substrate by performing a dry etching process with a hard mask of silicon oxide film serving as an etching mask in a dry etching device. At this time, a mixed gas of tetrafluoromethane (CF4), a hydrogen bromide gas (HBr), and a chlorine gas (Cl2) is used as an etching gas. The dry etching process is performed under the condition that a flow rate ratio is more than 0 and less than 0.04, the flow rate ratio being a value obtained by dividing a flow rate NF by a flow rate TF, the flow rate NF being a flow rate obtained by dividing a flow rate of the tetrafluoromethane by the number of fluorine atoms bonded to one molecule of the tetrafluoromethane, the flow rate TF being a total flow rate of the hydrogen bromide gas and the chlorine gas.

Abstract: A trench is formed at an exposed portion of a semiconductor substrate by performing a dry etching process with a hard mask of silicon oxide film serving as an etching mask in a dry etching device. At this time, a mixed gas of tetrafluoromethane (CF4), a hydrogen bromide gas (HBr), and a chlorine gas (Cl2) is used as an etching gas. The dry etching process is performed under the condition that a flow rate ratio is more than 0 and less than 0.04, the flow rate ratio being a value obtained by dividing a flow rate NF by a flow rate TF, the flow rate NF being a flow rate obtained by dividing a flow rate of the tetrafluoromethane by the number of fluorine atoms bonded to one molecule of the tetrafluoromethane, the flow rate TF being a total flow rate of the hydrogen bromide gas and the chlorine gas.

Abstract: An increase of the via resistance resulted due to the presence of the altered layer that has been formed and grown after the formation of the via hole can be effectively prevented, thereby providing an improved reliability of the semiconductor device. A method includes: forming a TiN film on the semiconductor substrate; forming an interlayer insulating film on a surface of the TiN film; forming a resist film on a surface of the interlayer insulating film; etching the semiconductor substrate having the resist film formed thereon to form an opening, thereby partially exposing the TiN film; plasma-processing the exposed portion of the TiN film to remove an altered layer formed in the exposed portion of the TiN film; and stripping the resist film via a high temperature-plasma processing.

Abstract: An increase of the via resistance resulted due to the presence of the altered layer that has been formed and grown after the formation of the via hole can be effectively prevented, thereby providing an improved reliability of the semiconductor device. A method includes: forming a TiN film on the semiconductor substrate; forming an interlayer insulating film on a surface of the TiN film; forming a resist film on a surface of the interlayer insulating film; etching the semiconductor substrate having the resist film formed thereon to form an opening, thereby partially exposing the TiN film; plasma-processing the exposed portion of the TiN film to remove an altered layer formed in the exposed portion of the TiN film; and stripping the resist film via a high temperature-plasma processing.