| 摘要 |
PROBLEM TO BE SOLVED: To prevent the copper atoms sputtered during bombardment process from diffusing into a inter-metal dielectrics layer, by forming a barrier layer on a copper layer which is exposed at the bottom part of a via opening before bombardment process is performed with the bottom part of the via opening until the copper layer is exposed. SOLUTION: A barrier layer 322 is formed on a surface comprising the inside surfaces of groove openings 318a and 318b, the inside surface of a via opening 312a, and the surface of a copper oxide layer 320. Then bombardment process 324 is performed. Copper atoms 304 ejected from a copper layer 304 under the bombardment process 324 are prevented from diffusing inside a first dielectrics layer 306 by the presence of a barrier layer 322b on the side wall. A barrier layer 322 at the bottom part of the via opening 312a is removed. Then a groove 318 and the via opening 312a are filled by vapor-deposition of a conductor layer 326. The conductor layer 326 is directly connected to the copper layer 304. Thus, the copper atoms cannot diffuse into a dielectrics layer, while the resistance of a via plug is lowered.
|
