Advances and Discoveries in Non-equilibrium Driven Nanomaterials and Thin Films: Advances inThin Film Oxides I/Recent Advances in Nanoscale Materials
Sponsored by: TMS Functional Materials Division, TMS: Advanced Characterization, Testing, and Simulation Committee, TMS: Thin Films and Interfaces Committee
Program Organizers: Ritesh Sachan, Oklahoma State University; Amit Pandey, Lockheed Martin Space; Saurabh Puri, VulcanForms Inc; Amber Srivastava, Indian Institute of Technology; Nuggehalli Ravindra, New Jersey Institute of Technology
Monday 2:00 PM
February 28, 2022
Room: 259B
Location: Anaheim Convention Center
Session Chair: Ritesh Sachan, Oklahoma State University; Saurabh Puri, Microstructure Engineering; David Bird, US Army
2:00 PM Invited
Hybrid Thin Film Interface for High Temperature Electronics Modules: Ajit Roy1; Sergei Shenogin1; John Ferguson1; John Jones1; Sabyasachi Ganguli1; 1Air Force Research Laboratory
The widely known primary failure mode in electronics modules, observed upon thermal cycling, is due to the material thermal expansion (CTE) mismatch induced stress build-up (thermal and electron-phonon coupling) at the interfaces of the electronics chip (die) with a metalized substrate to bond with the heat spreader (heat sink). A hybrid materials design of thin film interface for minimizing the interface CTE mismatch, as a replacement of Directly Bonded Copper (DBC) will be presented. A molecular dynamics analysis of the design of Zr/Cu hybrid yielded almost 50 percent reduction of CTE as compared to that of Cu. A multi-source magnetron sputtering is employed for the deposition of ~200 nm Zr/Cu hybrid thin film as the interface material. The data on thermal cycling testing of the hybrid interface will be presented.
2:30 PM Invited
Meta-stable Orthorhombic Phase of HfZrOx Thin Films for Ferroelectric Devices: Jiyoung Kim1; 1University of Texas at Dallas
Hf based oxides have several phases, such as monoclinic (thermodynamically stable phase at room temperature and 1 atm), tetragonal, cubic and orthorhombic. Recently, ferroelectric characteristics was discovered in Hf based oxide thin films with meta-stable noncentrosymmetric orthorhombic phase (space group: Pbc21). Because of Si process compatibility of Hf oxide, derivatives of Hf oxide have been extensively investigated for ferroelectric device applications. In this presentation, phase transformation to meta-stable orthorhombic phases from as-deposited amorphous thin films will be discussed along with their ferroelectric characteristics.
3:00 PM Invited
Identification of NV Centers in Nanodiamond through STEM-EELS/EDS: Bethany Hudak1; Rhonda Stroud1; 1Naval Research Laboratory
Single-photon-emitting color centers in nanodiamonds are an appealing architecture for quantum systems. In addition to strong single-photon photoluminescence from the color centers, diamond has many advantages, such as chemical inertness, mechanical hardness, and zero nuclear spin. Nitrogen-vacancy (NV) centers in nanodiamonds are among the most promising potential single-atom quantum systems. However, unambiguously locating a single NV center in a nanodiamond is challenging. Here, we perform simultaneous electron energy loss spectroscopy (EELS) and energy dispersive x-ray spectroscopy (EDS) spectrum imaging in an aberration-corrected scanning transmission electron microscope (STEM) to identify the NV centers, using the characteristic 282.4 eV peak in the C K-edge fine structure EELS data and the nitrogen signal at 0.39 keV in the EDS data. This atomic-scale identification of NV centers in the STEM is a potential first step towards in situ single-atom quantum device fabrication using the electron beam to control color center positioning.
3:30 PM Break
3:50 PM
Correlating Properties of Irradiation Produced Nanoscale Superlattices with Irradiation Condition Parameters by Combining Rate Theory and Kinetic Monte Carlo Simulations: Anton Schneider1; Yongfeng Zhang1; Chao Jiang2; Jian Gan2; 1University of Wisconsin Madison; 2Idaho National Laboratory
Void superlattices have been known to form in materials under irradiation for decades. Although the exact mechanisms of such lattice ordering remain debated, recent theoretical and experimental studies have clarified the critical roles of one-dimensional self-interstitial atoms (SIAs) diffusion and irradiation condition. Following the modeling approach developed in earlier works, the present study aims at providing a deeper understanding of the dependance of several key superlattice properties on irradiation conditions, by combining rate theory and kinetic Monte-Carlo simulations. The results show that key superlattice properties such as the lattice constant, the ordering, the critical dose of formation and the formation temperature window correlate strongly with irradiation dose rate, temperature, the degree of anisotropy of SIAs diffusion, and the presence of inert gas, and weakly with sink density. The correlations elucidated in this study provide deeper insights regarding superlattice formation and constitute a valuable step towards the development of tailor-made meta-materials.
4:15 PM
Growth of Complex Oxide Thin Films with Nanoscale Porosity by Pulsed Laser Deposition: Huiming Guo1; Xin Wang1; Alexander Dupuy1; Julie Schoenung1; William Bowman1; 1Department of Materials Science and Engineering, University of California, Irvine
Pulsed laser deposition (PLD) is a high-quality thin-film fabrication technique that can effectively translate crystal structure and stoichiometry of bulk functional complex oxide to nanometer-scale films with three-dimensional island structure. As a vital parameter in PLD, laser energy fluence (pulse energy per unit area), related to kinetic energy of adatoms, plays a critical role in crystal structure and morphology of thin films. Increasing energy fluence accelerates crystallite nucleation and growth even at low substrate temperature, therefore beneficial to single-phase thin film deposition of multicomponent oxides which otherwise would normally form secondary phases at elevated temperatures, like rock-salt complex concentrated oxide (CCO) (Co0.2Ni0.2Cu0.2Mg0.2Zn0.2)O [1]. In this work, we present an experimental study showing the lateral size of columnar grains, islands and nanopores as well as film thickness can be regulated by energy fluence [2], which will be used for customizing design of multiphase reaction interface in electrodes, sensors, catalysts, etc.
4:40 PM
Novel Bent-lattice Nanostructures in Crystallizing Amorphous Films Discovered by Transmission Electron Microscopy: Vladimir Kolosov1; 1Ural Federal University
Exotic thin crystals with unexpected transrotational nanostructure [1] are discovered by TEM bend-contour method for crystal growth in thin (10-100 nm) amorphous films. The unusual phenomenon can often be traced in situ in TEM by e-beam heating, annealing: regular internal (dislocation independent) bending of crystal lattice planes in a growing crystal. Such transrotation (translation of the unit cell is complicated by small rotation realized round an axis lying in the film plane) results in strong regular lattice orientation gradients (up to 300 degrees/µm) of different geometries: cylindrical, ellipsoidal, toroidal, saddle, etc. The transrotation phenomenon is the basis for novel lattice-rotation nanoengineering of functional, smart thin-film materials with the features suitable also for strain nanoengineering. Transrotational micro crystals can be grown in vital thin films, e.g. phase change materials (PCM) for memory, photonics enabling multifunctional properties. [1] V.Yu. Kolosov and A.R. Tholen, Acta Mater. 48 (2000) 1829