摘要 |
A process has been developed in which high aspect ratio contact holes can be successfully filled, without voids, using a composite metallization layer. After adhesive and barrier layers are deposited, an additional titanium adhesive layer is deposited, for purposes of improving the adhesion of subsequent, overlying metallizations to underlying device structures. A two step aluminum deposition process is then employed, using an initial cold deposition followed by a hot aluminum deposition. The hot aluminum deposition process results in complete filling of the high aspect ratio contact hole, and also allows the formation of a titanium-aluminum intermetallic layer at the interface of the titanium adhesive layer and the initial, cold aluminum deposition layer.
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