NEW PRECURSORS FOR ATOMIC LAYER DEPOSITION OF METALS

原子层沉积（ALD）是一种原子一个原子地构建材料薄层的方法，提供了对层的纳米结构和组成的精细控制。在ALD中，两种反应物蒸汽交替地提供给表面，在表面上它们反应形成薄层。薄膜具有高度均匀的厚度和成分和尖锐的界面，可以沉积在大面积，甚至在非常狭窄的孔内。然而，ALD过程仅对少数金属已知。我们建议发现和开发ALD前体和沉积许多金属的工艺，包括铬、锰、钽、铁、钌、钴、镍、铜和银，这些金属的ALD工艺是未知的。这些新的前驱体还将用于半导体微电子中感兴趣的金属化合物的ALD测试，例如氧化镧，氧化镨，氮化钛和氮化钽。更广泛的影响金属可以成为未来信息处理和存储设备的基础。铜、钴和钽薄膜的ALD可能成为半导体芯片上铜线进一步小型化的关键。在含有高介电常数金属氧化物的电容器中，金属氮化物需要用作共形扩散屏障和共形触点。未来的磁性数据存储可能与处理这些数据的硅半导体芯片集成在一起。建议的研究应有助于为实现这些希望提供科学基础，并为本科生、研究生和博士后提供相关培训。

Intellectual MeritAtomic layer deposition (ALD) is a method for constructing thin layers of materials atom by atom, providing exquisitely detailed control over the nano-structure and composition of the layers. In ALD, two reactant vapors are supplied alternately to a surface on which they react to form thin layers. Films with highly uniform thickness and composition and sharp interfaces can be deposited over large areas and even within very narrow holes. However, ALD processes are known for only a few metals. We propose to discover and develop ALD precursors and processes for depositing many metals, including chromium, manganese, tantalum, iron, ruthenium, cobalt, nickel, copper and silver, for which no ALD processes are known. These new precursors will also be tested for ALD of metal compounds of interest in semiconductor microelectronics, such as lanthanum oxide, praseodymium oxide, titanium nitride and tantalum nitride.Broader ImpactALD of metals may form the basis for future devices for both the processing and the storage of information. ALD of copper, cobalt and tantalum films may become a key to further miniaturization of copper wires on semiconductor chips. Metal nitrides are needed as conformal diffusion barriers and as conformal contacts in capacitors containing metal oxides with high dielectric constants. Future magnetic data storage may be integrated with the silicon semiconductor chips that process this data. The proposed research should help to supply the scientific base for the realization of these hopes, as well as providing relevant training for undergraduates, graduate students and post-doctoral fellows.