Fabrication Technology for Oxide Film Heterostructure Devices

In this STTR program, Structured Materials Industries, Inc. (SMI) and our partners are developing commercially viable fabrication technology for oxide heterostructure based nanoelectronic devices. Oxide heterostructures, consisting of a polar oxide such as LaAlO3 and a non-polar oxide such as SrTiO3, offer a novel route to building nanoelectronic devices. The benefits of these devices will include high information density, high speed, low power requirements, and the ability to operate in extreme environments of temperature and radiation. Prior research on oxide heterostructures was done using films deposited by pulsed laser deposition (PLD). In this STTR program, our technical approach uses Atomic Layer Deposition (ALD) to deposit the active materials. ALD has several advantages over competing PLD processes for fabricating all types of nanoelectronic devices, including, excellent control of film composition and thickness, excellent thickness uniformity over large wafer sizes, compatibility with nanoelectronic fabrication techniques, low cost-of-ownership and scalability to high volume production. In Phase I, our team demonstrated technical feasibility of producing oxide heterostructure devices, based on ALD of LaAlO3 thin films. In Phase II, we will build on these accomplishments and extend the technology to actual devices. BENEFIT: Transistors based on oxide heterostructures should be scalable to nano-dimensions, with corresponding improvements in speed and reduced power requirements. Oxide heterostructure transistors should also exhibit low noise, excellent high temperature performance and inherent radiation hardness, due to the fact that the active materials are wide bandgap oxides. Oxide heterostructure based memory devices would also exhibit high speed, low power requirements, high information density and inherent radiation hardness compared to present state of the art memory devices. In addition to logic and memory devices, we envision many other potential applications for oxide heterostructure devices, including high sensitivity radiation detectors, spintronic and related quantum computing devices, superconducting devices and proximity superconductivity devices. Our technical approach is to develop practical and economical fabrication technology for oxide heterostructure devices, both at R&D and commercial production scale. This will ensure that these materials are readily available to the research community at large, to foster widespread development of new devices and applications. The fact that our process technology is compatible with present microfabrication and with future nanofabrication ensures that the resulting devices will be rapidly transitioned to the market, and readily available in production quantities and at reasonable costs, for both military and commercial applications.