An interconnect structure for integrated circuits for copper wires in integrated circuits and methods for making the same are provided. Mn, Cr, or V containing layer forms a barrier against copper diffusing out of the wires, thereby protecting the insulator from premature breakdown, and protecting transistors from degradation by copper. The Mn, Cr, or V containing layer also promotes strong adhesion between copper and insulators, thus preserving the mechanical integrity of the devices during manufacture and use, as well as protecting against failure by electromigration of the copper during use of the devices and protecting the copper from corrosion by oxygen or water from its surroundings. In forming such integrated circuits, certain embodiments of the invention provide methods to selectively deposit Mn, Cr, V, or Co on the copper surfaces while reducing or even preventing deposition of Mn, Cr, V, or Co on insulator surfaces. Catalytic deposition of copper using a Mn, Cr, or V containing precursor and an iodine or bromine containing precursor is also provided.

The packing density of microelectronic devices has increased exponentially over the past four decades. Continuous enhancements in device performance and functionality have been achieved by the introduction of new materials and fabrication techniques. This thesis summarizes the thin film materials and metallization processes by chemical vapor deposition (CVD) developed during my graduate study with Professor Gordon at Harvard University. These materials and processes have the potential to build future generations of microelectronic devices with higher speeds and longer lifetimes. - Manganese Silicate Diffusion Barrier: Highly conformal, amorphous and insulating manganese silicate (MnSixOy) layers are formed along the walls of trenches in interconnects by CVD using a manganese amidinate precursor vapor that reacts with the surfaces of the insulators. These MnSixOy layers are excellent barriers to diffusion of copper, oxygen and water. - Manganese Capping Layer: A selective CVD manganese capping process strengthens the interface between copper and dielectric insulators to improve the electromigration reliability of the interconnects. High selectivity is achieved by deactivating the insulator surfaces using vapors containing reactive methylsilyl groups. Manganese at the Cu/insulator interface greatly increases the strength of adhesion between the copper and the insulator. - Bottom-up Filling of Copper and Alloy in Narrow Features: Narrow trenches, with widths narrow than 30 nm and aspect ratios up to 9:1, can be filled with copper or copper-manganese alloy in a bottom-up fashion using a surfactant-catalyzed CVD process. A conformal manganese nitride (Mn4N) layer serves as a diffusion barrier and adhesion layer. Iodine atoms chemisorb on the Mn4N layer and are then released to act as a catalytic surfactant on the surface of the growing copper layer to achieve void-free, bottom-up filling. Upon post-annealing, manganese in the alloy diffuses out from the copper and forms a self-aligned barrier in the surface of the insulator. - Conformal Seed Layers for Plating -Through-Silicon Vias: Through-silicon vias (TSV) will speed up interconnections between chips. Conformal, smooth and continuous seed layers in TSV holes with aspect ratios greater than 25:1 can be prepared using vapor deposition techniques. Mn4N is deposited conformally on the silica surface by CVD to provide strong adhesion at Cu/insulator interface. Conformal copper or Cu-Mn alloy seed layers are then deposited by an iodine-catalyzed direct-liquid-injection (DLI) CVD process.