| 摘要 |
PURPOSE: A reliable bit line contact structure having stable contact resistance in different regions and a method for forming the structure are provided. CONSTITUTION: On a semiconductor substrate(100) having a cell array region and a peripheral circuit region, a plurality of gate electrode patterns each having a polysilicon(120), a tungsten silicide(130), the first barrier metal(140), and a capping layer(150) are formed. Then, gate spacers(170) are formed on sides of the respective gate electrode patterns, and conductive pads(190) are formed between the gate patterns in the cell array region. An insulating layer(200) is then formed on an entire surface and selectively etched to form contact holes(210,220,230) therein. Next, a titanium layer is deposited on the insulating layer(200) and then heat-treated to form a titanium silicide layer(240) in bottoms of some contact holes(210,220). The titanium layer is removed, and the second barrier layer(250) is formed. Then, a tungsten layer(260) is formed enough to fill the contact holes(210,220,230).
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