Engineering Commons^™

Deep Learning-Guided Prediction Of Material’S Microstructures And Applications To Advanced Manufacturing, Jianan Tang

All Dissertations

Material microstructure prediction based on processing conditions is very useful in advanced manufacturing. Trial-and-error experiments are very time-consuming to exhaust numerous combinations of processing parameters and characterize the resulting microstructures. To accelerate process development and optimization, researchers have explored microstructure prediction methods, including physical-based modeling and feature-based machine learning. Nevertheless, they both have limitations. Physical-based modeling consumes too much computational power. And in feature-based machine learning, low-dimensional microstructural features are manually extracted to represent high-dimensional microstructures, which leads to information loss.

In this dissertation, a deep learning-guided microstructure prediction framework is established. It uses a conditional generative adversarial network (CGAN) …

Multilayered Planar Periodic Subwavelength Microstructures For Generating And Detecting Circularly Polarized Thermal Infrared Radiation, Samuel Lanning Wadsworth

Electronic Theses and Dissertations

Generation and detection of circularly-polarized (CP) radiation in the 8- to 12-μm band of the infrared (IR) spectrum is crucial for polarization sensing and imaging scenarios. There is very little naturally occurring CP radiation in the long-wave IR band, so that useful functionalities may be obtained by exploiting preferential radiation and transmission characteristics of engineered metamaterials. Conventional CP devices in the IR utilize birefringent crystals, which are typically bulky and expensive to manufacture. The operation of these devices is generally optimized at a single wavelength. Imaging in the long-wave IR is most often broadband, so that achromatic CP-device behavior is …

Microstructure And Electrical Performance Of Sputter-Deposited Hafnium Oxide (Hfo2) Thin Films, Brandon Adrian Aguirre

Open Access Theses & Dissertations

Hafnium oxide (HfO2) based dielectrics have been currently considered as the possible replacements for the traditional gate-oxide (SiO2) of the complementary metal-oxide semiconductor (CMOS) devices. The high dielectric constant, wide band gap, and thermal stability in contact with Si make HfO2 a potential material for application in CMOS devices. The performance of HfO2 as a gate oxide material, however, depends on its quality and interface structure with Si. In this work, HfO2 thin films have been deposited by rf sputtering onto Si(100) substrates under varying growth temperatures (Ts). The objective of the work is to understand the growth and microstructure …