公开(公告)号：JPH10107034A

公开(公告)日：1998-04-24

申请号：JP1196597

申请日：1997-01-07

Applicant: UNITED MICROELECTRONICS CORP

Inventor： DER-YUAN UU ,  II CHUN SHEN

IPC: H01L21/285 ,  H01L21/28 ,  H01L21/3205 ,  H01L21/336 ,  H01L21/768 ,  H01L21/8242 ,  H01L23/52 ,  H01L27/108 ,  H01L29/78

Abstract: PROBLEM TO BE SOLVED: To facilitate the patterning of a word line by a method wherein a gate is formed on a substrate to form the first metallic silicide layer on the gate and further to form the second metallic silicide layer having silicon in higher concentration than that of the first metallic silicone layer on the first metallic silicide layer. SOLUTION: A substrate having a gate oxide layer 24 and a polysilicon word line 26 is prepared so as to form a refractory metallic silicide layer i.e., a tungsten silicide is formed on the word line 26. Next, a silicon rich metallic silicide or pure silicon layer 30 is formed on the upper surface of the metallic silicide layer 28. This pure silicon layer 30 has silicon on higher concentration than that of the metallic silicide layer 28. Next, an uppermost oxide layer 32 is formed on the upper part surface of the pure silicon layer 30. Resultantly, the formation of tungsten oxide can be avoided thereby facilitating the patterning of the word line. Furthermore, the surface of the oxide layer can be made smooth.