Method of manufacturing spacers on sidewalls of titanium polycide gate

Abstract

Disclosed is a method for manufacturing a semiconductor device, more particularly to a method of forming a spacer on side-walls of a titanium polycide gate. The method for manufacturing the semiconductor device is as follows. There is provided a semiconductor substrate in which a gate oxide layer, a polysilicon layer, a titanium silicide layer and a patterned hard mask layer are sequentially formed. Herein, the titanium polycide gate is fabricated by an etching step employing the patterned hard mask. Afterward, the substrate is thermal-treated at temperature of 700˜750° C. according to a gate re-oxidation process, thereby forming a re-oxidation layer on side-walls of the gate and on the substrate surface. Next, an oxide layer for spacer is deposited on the resultant at process temperature of 350˜750 C., and a nitride layer is deposited on the oxide layer. Thereafter, a spacer is formed on side-walls of the gate and the hard mask layer by blanket-etching the nitride layer, the oxide layer and the re-oxidation layer.