1. Negative Capacitance Devices to Enable Low- Voltage/Low-Power Switching In Electronic Devices John G. Ekerdt, University of Texas at Austin, DMR 1207342 The efforts to epitaxially integrate ferroelectric BaTiO 3 (BTO) on SrTiO 3 (STO)-buffered Si(001) have been demonstrated using MBE. However, high temperature MBE growth results in a significant amorphous layer between STO and Si. Such a layer is undesirable in many applications. ALD offers a low temperature growth that results in no interlayer. In addition, for industrial applications, ALD has advantages over MBE due to its high step coverage, scalability, and low cost. We have grown c-axis oriented epitaxial BTO at 225  C using ALD on 1.6-nm STO-buffered Si(001). A 5- min vaccum anneal at 600 °C improved BTO crystallinity. The BTO films have a good degree of crystallinity and no amorphous layer was observed at the STO/Si interface. Annealing using a lower ramping rate (5 °C/min) is able to maintain the c-axis orientated tetragonal structure. We expect the ALD method of growing c-axis oriented epitaxial BTO on STO-buffered Si(001) at low temperature to be a potential way to fabricate the negative capacitance gate oxide structure on Si with no amorphous layer between STO and Si. PFM measurements will be performed to explore BTO thin film ferroelectric properties. (Top) STEM image of a 17 nm ALD-grown BTO on four unit cell MBE-grown STO-buffered Si(001) after a 5 min vacuum anneal at 600 °C, indicating no amorphous interlayer between STO and Si. Ngo, Posadas, McDaniel, Hu, Bruley, Yu, Demkov, Ekerdt, Appl. Phys. Lett. 104, 082910 (2014). (Bottom) C-V (at 100 kHz) characteristics of an as- deposited 18 nm BTO film on 1.6 nm STO-buffered Si(001). The dielectric constant of the BTO/STO stack on Si was estimated to be about 660. (Reproduced with permission from Applied Physics Letters. Copyright 2014, AIP Publishing LLC.)

2. (Top) AIW 2014 students excited for a materials research experience with the one of the faculty research groups; (Bottom) Five AIW students learn to analyze x-ray photoelectron spectroscopy data to identify what elements are present in their thin-film sample. We have continued the Demkov-initiated outreach program Alice in Wonderland (AIW), initially funded under the NSF grant DMR-0606464. The program is aimed at attracting high-school female students to physical sciences and engineering; in collaboration with local high schools, the students spend summers in research groups at the University of Texas at Austin and participate in “real science” in a supportive environment. Students learn from the hands on experience about advanced subjects such as nanoparticle properties, atomic force microscopy (AFM), atomic layer deposition (ALD), and x-ray photoelectron spectroscopy (XPS). They interact with a large group of faculty, graduate and undergraduate students. We have received tremendous positive feedback from both students and parents of the AIW participants. One student writes, “THANK YOU! We appreciated the time you gave to support my education and spark my interests in science and its applications.” Another student writes, “…I loved chemical engineering, so much so, that I'm now planning on applying to the Cockrell School of Engineering as a ChE major.” The AIW program has continued to grow over the past few years, with a record- high 24 high school students in 2014. http://www.ph.utexas.edu/aliceinwonderland/ Negative Capacitance Devices to Enable Low- Voltage/Low-Power Switching In Electronic Devices John G. Ekerdt, University of Texas at Austin, DMR 1207342