具有金属闸极之半导体结构及其制造方法;SEMICONFUCTOR STRUCTURE WITH METAL GATE AND MANUFACTURING METHOD THEREOF

摘要

一种用于制造一金属闸极结构之方法，其包括：在一闸极渠沟中形成一高介电常数(k)介电层；在该高k介电层上形成一蚀刻停止层(etch stop)；藉由以一原子层沈积(ALD)操作于该蚀刻停止层上形成具有一三合层结构的一功函数调整层，该三合层依序具有一晶界操控层、一掺杂层、及一封盖层，该晶界操控层用以让一掺杂原子穿透其本身，该掺杂层用以将该掺杂原子提供给该晶界操控层，且该封盖层用以防止该掺杂层氧化；以及填入金属以填平该闸极渠沟。该晶界操控层系藉由ALD操作在各种温度(例如自约摄氏200度至约350度)下制备。; forming an etch stop over the high-k dielectric layer; forming a work function adjusting layer over the etch stop by forming a tri-layer by an atomic layer deposition (ALD) operation with a sequence of a grain boundary engineering layer configured to allow a dopant atom to penetrate there through, a doping layer configured to provide the dopant atom to the grain boundary engineering layer, and a capping layer configured to prevent the doping layer from oxidation; and filling metal to level up the gate trench. The grain boundary engineering layer is prepared by the ALD operation under various temperatures such as from about 200 to about 350 degrees Celsius.