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Electrical and Computer Engineering

Qiangfei Xia

Selected Works

2014

Articles 1 - 3 of 3

Full-Text Articles in Engineering

Concentric Rings Of Polystyrene And Titanium Dioxide Nanoparticles Patterned By Alternating Current Signal Guided Coffee Ring Effect, Jinhua Mu, Peng Lin, Qiangfei Xia Jan 2014

Concentric Rings Of Polystyrene And Titanium Dioxide Nanoparticles Patterned By Alternating Current Signal Guided Coffee Ring Effect, Jinhua Mu, Peng Lin, Qiangfei Xia

Qiangfei Xia

The authors studied the surface deposition of nanoparticles by introducing an alternating current (AC) signal into the millimeter-sized nanoparticle droplet. For both polystyrene (PS) in deionized (DI) water and titanium dioxide (TiO2) in toluene, the nanoparticles self-assembled into regular concentric rings over a larger area on the substrate during the droplet drying process. The patterned area decreased, and the inter-ring spacing increased with higher AC frequencies for the TiO2/toluene system, while those for the PS/DI water system only changed slightly. The frequency dependent pattern formation was interpreted by the interaction between different factors such as capillary flow and the AC …


Single- And Bi-Layer Memristive Devices With Tunable Properties Using Tiox Switching Layers Deposited By Reactive Sputtering, Hao Jiang, Qiangfei Xia Jan 2014

Single- And Bi-Layer Memristive Devices With Tunable Properties Using Tiox Switching Layers Deposited By Reactive Sputtering, Hao Jiang, Qiangfei Xia

Qiangfei Xia

The authors systematically studied reactive sputtering deposition of TiOx thin films using a mixture of Ar and O2 gases under different ratios of O2 flow. As directly revealed by X-ray photoelectron spectroscopy, the deposition changed from a metallic Ti target mode to an oxide target mode when the O2 flow ratio was beyond 40%, resulting in TiOx thin films with different chemical compositions. Consequently, metal/oxide/metal devices with a single TiOx layer exhibited a broad spectrum of electrical characteristics such as Ohmic, rectifying, and memristive behavior. The reactive sputtering deposited TiOx thin films were also used in a bilayer memristive device …


3d Integration Of Planar Crossbar Memristive Devices With Cmos Substrate, Peng Lin, Shuang Pi, Qiangfei Xia Jan 2014

3d Integration Of Planar Crossbar Memristive Devices With Cmos Substrate, Peng Lin, Shuang Pi, Qiangfei Xia

Qiangfei Xia

Memristive devices are promising building blocks for enhanced CMOS hardware in data storage and computing. Nanoimprint lithography (NIL) has been an enabling technology in the past decade for exploring novel devices and circuits. In this paper, the authors review the progress and technical aspects of the fabrication and integration of memristor crossbar arrays using NIL. Since the key component of successful fabrication is the imprint mold, the material selection, master mold fabrication, anti-sticking treatment and cleaning are first discussed. The requirements and composition of imprint resists, in particular low-viscosity liquid resists that cross-link upon ultraviolet light radiation, are investigated next. …