Nitride Phosphors for Low Voltage Cathodoluminescence Devices

ABSTRACTUndoped and Zn doped InGaN microcrystals were synthesized by a two-step method. The InGaN microcrystals have a wurtzite structure and brownish body color. The InGaN samples prepared at 900°C did not contain a metal In phase. The InGaN:Zn microcrystals showed blue photoluminescence (PL) at 77K different from that of GaN:Zn. Reflectivity and photoluminescence excitation (PLE) measurement showed that the fundamental absorption edge of the InGaN:Zn phosphors is 3.47 eV, which implies that the In content in the InGaN:Zn phosphors is less than 0.2%. GaN:Zn and InGaN:Zn showed a Zn related PLE peak at 3.34 eV. InGaN and InGaN:Zn showed an In related PLE peak at 3.14 eV. When the InGaN:Zn samples were selectively excited at 3.15 eV, an In-related emission band centered at 2.2 eV emerged. The InGaN:Zn phosphors mounted on vacuum fluorescent displays (VFDs) showed room-temperature blue cathodoluminescence (CL) and the CL peak shifted slightly toward the low energy compared to that of the GaN:Zn phosphors because of the superimposed In related band. The InGaN:Zn phosphors had a luminance of 50 cd/m2 and a luminance efficiency of 0.03 lm/W at an anode voltage of 50 V.

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Low-energy room-temperature optical switching in mixed-dimensionality nanoscale perovskite heterojunctions

Science Advances ◽

10.1126/sciadv.abf1959 ◽

2021 ◽

Vol 7 (18) ◽

pp. eabf1959

Author(s):

Ji Hao ◽

Young-Hoon Kim ◽

Severin N. Habisreutinger ◽

Steven P. Harvey ◽

Elisa M. Miller ◽

...

Keyword(s):

Optical Switching ◽

Room Temperature ◽

Optical Memory ◽

Low Energy ◽

Optical Measurements ◽

Ion Migration ◽

Metal Halide Perovskite ◽

Conductance Changes ◽

Optical Domain ◽

Walled Carbon Nanotubes

Long-lived photon-stimulated conductance changes in solid-state materials can enable optical memory and brain-inspired neuromorphic information processing. It remains challenging to realize optical switching with low-energy consumption, and new mechanisms and design principles giving rise to persistent photoconductivity (PPC) can help overcome an important technological hurdle. Here, we demonstrate versatile heterojunctions between metal-halide perovskite nanocrystals and semiconducting single-walled carbon nanotubes that enable room-temperature, long-lived (thousands of seconds), writable, and erasable PPC. Optical switching and basic neuromorphic functions can be stimulated at low operating voltages with femto- to pico-joule energies per spiking event, and detailed analysis demonstrates that PPC in this nanoscale interface arises from field-assisted control of ion migration within the nanocrystal array. Contactless optical measurements also suggest these systems as potential candidates for photonic synapses that are stimulated and read in the optical domain. The tunability of PPC shown here holds promise for neuromorphic computing and other technologies that use optical memory.

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Great advantages of using low voltage HR-SEM in spatial resolution and sensitivity for low energy X-ray analyses

European Microscopy Congress 2016: Proceedings ◽

10.1002/9783527808465.emc2016.6426 ◽

2016 ◽

pp. 913-914

Author(s):

Asahina Shunsuke ◽

Takahashi Hideyuki ◽

Takakura Masaru ◽

Ferdi Schüth ◽

Terasaki Osamu

Keyword(s):

Spatial Resolution ◽

Low Voltage ◽

Low Energy ◽

X Ray

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Synthesis of CaWO4:(Eu3+,Tb3+) Thin Films by a Two-Step Method at Room Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.710.170 ◽

2013 ◽

Vol 710 ◽

pp. 170-173

Author(s):

Lian Ping Chen ◽

Yuan Hong Gao

Keyword(s):

Thin Film ◽

Thin Films ◽

Phase Composition ◽

Room Temperature ◽

Electrochemical Techniques ◽

Luminescent Properties ◽

X Ray Diffraction ◽

Step Method ◽

X Ray ◽

Rare Earth Doped

It is hardly possible to obtain rare earth doped CaWO4thin films directly through electrochemical techniques. A two-step method has been proposed to synthesize CaWO4:(Eu3+,Tb3+) thin films at room temperature. X-ray diffraction, energy dispersive X-ray analysis, spectrophotometer were used to characterize their phase, composition and luminescent properties. Results reveal that (Eu3+,Tb3+)-doped CaWO4films have a tetragonal phase. When the ratio of n (Eu)/n (Tb) in the solution is up to 3:1, CaWO4:(Eu3+,Tb3+) thin film will be enriched with Tb element; on the contrary, when the ratio in the solution is lower than 1:4, CaWO4:(Eu3+,Tb3+) thin film will be enriched with Eu element. Under the excitation of 242 nm, sharp emission peaks at 612, 543, 489 and 589 nm have been observed for CaWO4:(Eu3+,Tb3+) thin films.

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Semiconductor Nanocrystal Floating-gate Memory Devices

MRS Proceedings ◽

10.1557/proc-830-d5.1 ◽

2004 ◽

Vol 830 ◽

Cited By ~ 5

Author(s):

P. Dimitrakis ◽

P. Normand

Keyword(s):

Low Voltage ◽

Ion Beam ◽

Low Energy ◽

Floating Gate ◽

Device Performance ◽

Memory Devices ◽

Research Directions ◽

Semiconductor Nanocrystal ◽

Floating Gate Memory ◽

Attractive Option

ABSTRACTCurrent research directions and recent advances in the area of semiconductor nanocrystal floating-gate memory devices are herein reviewed. Particular attention is placed on the advantages, limitations and perspectives of some of the principal new alternatives suggested for improving device performance and reliability. The attractive option of generating Si nanocrystal memories by ion-beam-synthesis (IBS) is discussed with emphasis on the ultra-low-energy (ULE) regime. Pertinent issues related to the fabrication of low-voltage memory cells and the integration of the ULE-IBS technique in manufactory environment are discussed. The effect on device performance of parasitic transistors that form at the channel corner of shallow trench isolated transistors is described in details. It is shown that such parasitic transistors lead to a substantial degradation of the electrical properties of the intended devices and dominates the memory behavior of deep submicronic cells.

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Ultra-low Voltage Low Power Active-RC Filters and Amplifiers for Low Energy RF Receivers

10.1007/978-3-030-90103-5 ◽

2022 ◽

Author(s):

Lucas Compassi Severo ◽

Wilhelmus Adrianus Maria Van Noije

Keyword(s):

Low Power ◽

Low Voltage ◽

Low Energy ◽

Rf Receivers

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A 0.19-V minimum input low energy level shifter for extremely low-voltage VLSIs

2015 IEEE International Symposium on Circuits and Systems (ISCAS) ◽

10.1109/iscas.2015.7169305 ◽

2015 ◽

Cited By ~ 14

Author(s):

Ryo Matsuzuka ◽

Tetsuya Hirose ◽

Yuzuru Shizuku ◽

Nobutaka Kuroki ◽

Masahiro Numa

Keyword(s):

Energy Level ◽

Low Voltage ◽

Low Energy ◽

Level Shifter

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Preparation of Whey-Based Banana Beverage and its Quality Evaluation

Himalayan Journal of Science and Technology ◽

10.3126/hijost.v5i01.42140 ◽

2021 ◽

Vol 5 (01) ◽

pp. 60-66

Author(s):

Kunjal Shrestha ◽

Abhishek Dahal

Keyword(s):

Sensory Analysis ◽

Room Temperature ◽

Storage Time ◽

Value Added ◽

Body Color ◽

Overall Acceptability ◽

A Value ◽

Banana Juice ◽

Nutritional Qualities ◽

The One

A value-added functional beverage was formulated utilizing unprocessed whey with excellent nutritional qualities and bland flavors; along with banana juice and the required amount of sugar. Five different formulations were prepared with varying proportions of whey, banana juice, and sugar. Sensory analysis was carried out for all five formulations and based on statistical analysis the one which showed the highest value for body, color, flavor, taste, and overall acceptability was selected for further analysis (85% liquid whey and 15% banana juice). The shelf-life of the final product was observed for 30 days at room temperature (25±5°C) and refrigerated temperature (7±1ºC). A significant variation in body, color, flavor, taste, and overall acceptability were observed by varying the composition of whey and banana juice (p<0.05). The beverage was pasteurized at 82.5°C for 20 min and stored at normal (25±5°C) and refrigerated (7±1°C) for 30 days. The effects of storage time and temperature on physicochemical (TSS, pH, acidity) and microbial (TPC, yeast & mold count) properties were evaluated. Out of five formulations, the one selected via sensory analysis had TSS of 12.4°Bx, total solids 14.21%, 0.302% acidity, pH 5.72, 5.087% reducing sugar, 0.53% protein, 0.56% ash, 0.87% crude fiber, 184.43mg potassium (mg/100gm) and 0.912mg vitamin C in 100 ml. The prepared beverage was stored for 30 days under refrigerated and normal conditions, and changes in TSS, pH and acidity were observed: 12.413.3%, 5.72-5.214, 0.32-0.43%, and 12.4-13.8%, 5.72-4.64, 0.32-0.68% respectively. Overall analysis showed that the beverage prepared with 85% liquid whey and 15% banana juice could be stored for 30 days under refrigerated conditions without the addition of preservatives.

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