Integration of in situ RHEED with magnetron sputter deposition for atomic layer controlled growth

Epitaxial thin films continue to be one of the most promising topics within electronic materials research. Sputter deposition is one process by which these films can be formed and is a widely used growth technique for a large range of technologically important material systems. Epitaxial films of carbides, nitrides, metals, oxides and more can all be formed during the sputter process which offers the ability to deposit smooth and uniform films from the research level up to an industrial scale. This tunable kinematic deposition process excels in easily adapting for a large range of environments and growth procedures. Despite the vast advantages associated with sputter deposition, there is a significant lack of in situ analysis options during sputtering. In particular, the area of real time atomic layer control is severely deficient.;Atomic layer controlled growth of epitaxial thin films and artificially layered superlattices is critical for both understanding their emergent phenomena and engineering novel material systems and devices. Reflection high-energy electron diffraction (RHEED) is one of the most common in situ analysis techniques during thin film deposition that is rarely used during sputtering due to the strong permanent magnets in magnetron sputter sources and their effect on the RHEED electron beam. In this work we have solved this problem and designed a novel way to deter the effect of the magnets for a wide range of growth geometries and demonstrate the ability for the first time to have layer by layer control during sputter deposition by in situ RHEED. A novel growth chamber that can seamlessly change between pulsed laser deposition and sputtering with RHEED for the growth of complex heterostructures has been designed and implemented. Epitaxial thin films of LaAlO3, La1-xSrxMnO3, and SrRuO3 have all been deposited by sputtering and shown to exhibit clear and extended RHEED oscillations. To solve the magnet issue, a finite element model has been constructed to predict and avoid the deflection of the electron beam in many geometries. Together, this creates the possibility for RHEED to become a widely used real time analysis tool with sputter deposition with far reaching applications and potential.