Browsing by Author "Zhang, Wei"

Now showing 1 - 7 of 7

An Electronic Synapse Device Based on Solid Electrolyte Resistive Random Access Memory
(2015-08-01)
Zhang, Wei
;
Hu, Ying
;
Chang, Ting-Chang
;
Chang, Kuan-Chang
;
Tsai, Tsung-Ming
The multilevel capability of solid electrolyte resistive random access memory (RRAM) with a Pt/GeSO/TiN structure was explored for potential use as a synapse device. By varying the cutoff voltage during the dc I-V cycles or the ac pulse programming voltage amplitudes, continuous multilevel conductance states were obtained. The reference Pt/GeO/TiN RRAM was fabricated to certify the multilevel capability and was due to the character of the GeS solid electrolyte. Finally, the property of gradual conductance states was exploited to demonstrate spike-timing-dependent plasticity learning, which suggests device\'s potential for use as an electronic synapse device for neuromorphic systems.
Effects of Varied Negative Stop Voltages on Current Self-Compliance in Indium Tin Oxide Resistance Random Access Memory
(2015-06-01)
Lin, Chih-Yang
;
Chang, Kuan-Chang
;
Chang, Ting-Chang
;
Tsai, Tsung-Ming
;
Pan, Chih-Hung
We have previously investigated the automatic current compliance property for indium tin oxide (ITO) resistance random access memory (RRAM). Traditionally, for the purpose of protecting RRAM, it is necessary to set equipment current compliance during the set and forming processes of RRAM devices. ITO RRAM devices, however, have an intrinsic capability to limit their current. This letter examines this ITO RRAM current compliance in depth by applying a varied stop-voltage measurement method, where different negative stop voltages were adopted to manipulate oxygen ions. Combined with material analysis and conduction current fitting, a model was established.
Fluorous and traceless synthesis of substituted indole alkaloids
(2007-11-01)
Lin, Mei-Jung
;
Zhang, Wei
;
Sun, Chung-Ming
;
應用化學系
;
Department of Applied Chemistry
The fluorous traceless synthesis of substituted indole alkaloids is carried out first by attaching the 3-(perfluorooctyl)propanol with Boc protected L-tryptophan. The reaction of perfluoroalkyl (Rfh)-tagged tryptophan esters with various aldehydes undergos Pictet-Spengler reaction to give cis and trans stereoisomers of tetrahydro-beta-carbolines. The nucleophilic addition of the piperidine nitrogen across various isocyanates is followed by the cyclization of ureas and simultaneous rupture of the fluorous tag to afford the hydantoin ring fused tetrahydro-beta-carbolines. All the fluorous-tag compounds are purified by solid-phase extraction (SPE) through Fluoro Flash cartridges.
Improvement of Resistive Switching Characteristic in Silicon Oxide-Based RRAM Through Hydride-Oxidation on Indium Tin Oxide Electrode by Supercritical CO2 Fluid
(2015-06-01)
Chang, Kuan-Chang
;
Tsai, Tsung-Ming
;
Chang, Ting-Chang
;
Zhang, Rui
;
Chen, Kai-Huang
Supercritical carbon dioxide (SCCO2) fluid technology was applied to indium-tin-oxide (ITO) electrode to improve the resistive switching characteristic of silicon oxide RRAM through hydride oxidation for the first time. We found device power consumption can be effectively reduced so that side effects can be also restricted under device operation. By applying SCCO2 fluid, more oxygen ions will be introduced into the ITO electrode and thus the participation of net oxygen ions in the RRAM redox reaction will increase. Fourier transform spectroscopy and X-ray photoelectron spectroscopy were used to confirm hydride oxidation on ITO electrode. Combined with the current fitting results, we proposed a reaction model to explain the improvement of resistive switching in RRAM by SCCO2 fluids.
Mechanism of Triple Ions Effect in GeSO Resistance Random Access Memory
(2015-06-01)
Zhang, Wei
;
Hu, Ying
;
Chang, Ting-Chang
;
Tsai, Tsung-Ming
;
Chang, Kuan-Chang
In this letter, a triple-ion redox reaction has been proposed and investigated in GeSO-based resistance random access memory. Continuous multiresistance states can be obtained by applying a series of increasing cutoff voltages in both set and reset processes. Using data retention tests, these multistates in the set and reset processes were confirmed to be stable. The conduction mechanism gradually changed during reset process from space charge limited current to Schottky emission. A triple-ion reaction model has been proposed to reveal the chemical reaction properties in the resistive switching process.
Sequential [3+2] and [4+2] Cycloadditions for Stereoselective Synthesis of a Novel Polyheterocyclic Scaffold
(2013-07-01)
Lu, Qing
;
Xin Huang
;
Song, Gonghua
;
Sun, Chung-Ming
;
Jasinski, Jerry P.
A strategy of combining [3 + 2] cycloaddition and intramolecular Diels-Alder reaction is developed for the [3 + 2] cycloaddition of azomethine ylides and maleimides were derivatized for intramolecular Diels-Alder reaction of furan to form highly condensed heterocyclic products as racemic single diastereomers.
Using cloud computing integrated architecture to improve delivery committed rate in smart manufacturing
(1970-01-01)
Xia, Ting
;
Zhang, Wei
;
Chiu, W. S.
;
Jing, Changqiang
;
資訊管理與財務金融系註：原資管所+財金所
This paper proposed an integrated architecture and case study highlighting practices for developing cloud computing system in smart manufacture. It developed an electronic purchase order web-based system with four business units. The research method is based on applying Rational Unified Process and ICAM DEFinition Model (IDEF). It uses scenario and IDEF model to represent the user requirements, and object oriented technology to construct smart system. It also drives critical Key Performance Indexes (KPI) to evaluate the benefits of enterprises adopting the proposed architecture. The result shows that this architecture and methodology can reduce process time, reduce processing cost, improve accuracy, efficiency.