Electroless deposition process on a silicide contact

Abstract

Embodiments as described herein provide methods for depositing a material on a substrate during electroless deposition processes, as well as compositions of the electroless deposition solutions. In one embodiment, the substrate contains a contact aperture having an exposed silicon contact surface. In another embodiment, the substrate contains a contact aperture having an exposed silicide contact surface. The apertures are filled with a metal contact material by exposing the substrate to an electroless deposition process. The metal contact material may contain a cobalt material, a nickel material, or alloys thereof. Prior to filling the apertures, the substrate may be exposed to a variety of pretreatment processes, such as preclean processes and activations processes. A preclean process may remove organic residues, native oxides, and other contaminants during a wet clean process or a plasma etch process. Embodiments of the process also provide the deposition of additional layers, such as a capping layer.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims benefit of U.S. Ser. No. 60 / 663,493, filed Mar. 18, 2005 (9916L), U.S. Ser. No. 60 / 683,599, filed May 23, 2005 (9916L.02), U.S. Ser. No. 60 / 703,538, filed Jul. 29, 2005 (9916L.03), U.S. Ser. No. 60 / 703,633, filed Jul. 29, 2005 (9916L.04), U.S. Ser. No. 60 / 709,564, filed Aug. 19, 2005 (9916L.05), U.S. Ser. No. 60 / 754,230, filed Dec. 27, 2005 (9916L.06), and U.S. Ser. No. 60 / 731,624, filed Oct. 28, 2005 (10659L), which are all herein incorporated by reference in their entirety.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] Embodiments of the invention generally relate to methods for depositing materials on substrates, and more specifically to methods for filling apertures within a high aspect ratio contact. [0004] 2. Description of the Related Art [0005] Multilevel, 45 nm node metallization is one of the key technologies for the next generation of very large scale integration (VLSI). The multil...

AI Technical Summary

Benefits of technology

[0017] In one embodiment, a composition of a cobalt deposition solution is provided which contains a cobalt source at a concentration within a range from about 1 mM (millimolar, millimole/L) to about 150 mM, a reducing agent source at a concentration within a range from about 1 mM to about 100 mM, and a chelating agent source at a concentration within a range from about 10 mM to about 500 mM. In another example, the cobalt deposition solution contains the cobalt source at a concentration within a range from about 10 mM to about 100 mM, the reducing agent source at a concentration within a range from about 5 mM to about 50 mM, and the chelating agent source at a concentration within a range from about 50 mM to about 300 mM. In another example, the cobalt deposition solution contains the cobalt source at a concentration within a range from about 20 mM to about 80 mM, the reducing agent source at a concentration within a range from about 10 mM to about 40 mM, and the chelating agent source at a concentration within a range from about 75 mM to about 250 mM. In another example, the cobalt deposition solution contains the cobalt source at a concentration of about 35 mM, the reducing agent source at a concentration of about 25 mM, and the chelating agent source at a concentration of about 150 mM. The chelating agent source may include citric acid, lactic acid, glycine, ethanolamine, diethanolamine, triethanolamine, salts thereof, derivatives thereof, or combinations thereof. In one example the reducing agent source comprises dimethylamine-borane complex. Other examples provide that the composition contains boric acid, saccharin, ammonium fluoride, or tetramethylammonium fluoride. A pH adjusting agent, such as TMAH, may be added to provide the cobalt deposition solution having a pH value within a range f

Problems solved by technology

Although copper and tungsten are popular interconnect materials, deposition processes for depositing these materials may suffer by forming a void or a seam within the contact plug, as illustrated in FIG. 1C.

Defects, such as a seam or void 114, may cause a series of problems during the fabrication of electronic devices depicted herein.

However, a more serious obstacle during fabrication is the displacement of voids from one layer to the next.

Ultimately, the defects in conductive layer 112 can affect the device yield of the fabricated substrate.

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