scholarly journals Ceramic Materials (Phosphors) for Display Applications

2010 ◽  
Vol 13 (1-2) ◽  
pp. 1
Author(s):  
K.V.R. Murthy ◽  
Ch. Atchyutha Rao ◽  
K. Suresh ◽  
N.V. Poornachandra Rao ◽  
B. Subba Rao ◽  
...  
Keyword(s):  
Contrast Ratio ◽  
Ultra Violet ◽  
Ceramic Materials ◽  
High Energy ◽  
High Definition ◽  
Luminescence Efficiency ◽  
Cathode Ray Tube ◽  
Plasma Display ◽  
Luminescence Characteristics ◽  
Vacuum Ultra Violet

<p>Phosphors the ceramic materials should able to work in tough environment surrounded and bombarded by high energy Vacuum Ultra Violet (VUV), UV or electron beam radiations in any discharge tube. The plasma display panel (PDP) is increasingly gaining attention over conventional cathode ray tube (CRT)- based TVs as a medium of large format (60+”) television (TV), particularly high definition TVs (HDTVs). Improvements have been made not only in size but also in other areas such as resolution, luminescence efficiency, brightness, contrast ratio, power consumption, and cost reduction. The formation of a phosphor host and doping process by solid solution is critical and is highly dependent on the reaction temperature and conditions. Since the purity of starting chemicals is very important to the synthesis of phosphors, the starting chemicals are typically 99.9%, 99.999% in purity. Required amounts of starting ingredients are mixed in the presence of an appropriate flux (if necessary) and fired at high temperatures (1200 °C) in air or in a controlled atmosphere (N<sub>2</sub>, C, CO, or N<sub>2</sub> with 2-5% of H<sub>2</sub>). The present paper reports the synthesis and luminescence characteristics of different ceramic materials (phosphors) for display applications.</p>

Low Thermal Budget Processing Of Organic Dielectrics

1995 ◽  
Vol 381 ◽  
Author(s):  
R. Sharangpani ◽  
R. Singh ◽  
K. C. Cherukuri ◽  
R.P.S. Thakur
Keyword(s):  
High Performance ◽  
Ultra Violet ◽  
High Energy ◽  
Curing Temperature ◽  
Film Stress ◽  
Thermal Budget ◽  
Low Thermal Budget ◽  
Rapid Isothermal Processing ◽  
Organic Dielectrics ◽  
Vacuum Ultra Violet

AbstractLow dielectric constant organic materials are ideal for use as interconnect dielectrics forintegrated circuits. As compared to silicon dioxide, organic dielectrics with K <3.84 reducepower dissipation, crosstilk and RC delays in interconnects. Curing is essential afterdeposition of these materials to initiate polymerization reactions and form films of desirableelectrical properties. For high performance and reliability, low thermal budget processing isa necessity. Rapid isothermal processing (RIP) based on the use of dual spectral sources isa potential technique to lower the thermal budget. In this paper, we demonstrate the role ofphotoeffects in the curing of polyimide films (K∼2.6) using a rapid isothermal processor witha dual spectral source (Tungsten Halogen and vacuum ultra violet (VUV) lamps) as a sourceof optical and thermal energy. Lamp configurations that allowed a greater availability of ultraviolet and vacuum ultra violet photons on the film to initiate physical and chemical processesallowed a lower curing temperature to achieve the same level of immidization. Furthermore, these samples also gave the lowest leakage current and film stress. Therefore, the rapidheating and cooling features of rapid isothermal processing in conjunction with lowerprocessing temperature through the use of high energy photons to enhance surface reactionsgive superior film properties

Defect Reduction and Improved Device Performance using Rapid Isothermal Diffusion in Silicon

1997 ◽  
Vol 469 ◽  
Author(s):  
L. Vedula ◽  
R. Singh ◽  
D. Ratakonda ◽  
A. Rohatgi ◽  
S. Narayanan
Keyword(s):  
Fundamental Property ◽  
Ultra Violet ◽  
High Energy ◽  
Processing Temperature ◽  
Defect Reduction ◽  
Isothermal Diffusion ◽  
Junction Formation ◽  
Diffusion Metallization ◽  
Rapid Isothermal Processing ◽  
Vacuum Ultra Violet

ABSTRACTQuantum photoeffects associated with photons of wavelength less than 0.8 micron lead to higher bulk and surface diffusion coefficients. We have exploited this fundamental property in designing rapid isothermal processing (RIP) systems for shallow junction formation in silicon. A detailed comparative study of diffusion, metallization and CVD with and without high energy photons has been carried out. The results show that microscopic defects, cycle time and processing temperature is lower than what can be achieved byconventional methods is realized by using photons in the ultra violet (UV) and vacuum ultra violet (VUV) spectrum.

scholarly journals Luminescence Quenching Behavior of Hydrothermally Grown YVO4:Eu3+ Nanophosphor Excited under Low Temperature and Vacuum Ultra Violet Discharge

Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3270
Author(s):  
Mihye Wu ◽  
Hyemin Park ◽  
Eun Gyu Lee ◽  
Sanghun Lee ◽  
Yu Jin Hong ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Low Temperature ◽  
Energy Transfer Process ◽  
Ultra Violet ◽  
Luminescence Quenching ◽  
Hydroxyl Groups ◽  
Hydrothermal Processing ◽  
Luminescence Efficiency ◽  
Post Annealing ◽  
Vacuum Ultra Violet

The luminescence quenching behavior and energy transfer process in hydrothermally grown Eu3+-doped YVO4 nanophosphors were studied using low temperature photoluminescence spectroscopy. The luminescence efficiency of nanophosphor is dependent on the acidity of its solution media and the post annealing condition after hydrothermal processing. The overall results suggest that the abnormal luminescence behavior of Eu3+-doped nanocrystalline YVO4 under low temperature photoexcitation is due to the incorporated non-radiative hydroxyl groups often encountered in hydrothermal synthesis as well as to the inefficient energy transfer to luminescent ions from vanadate groups.

Vacuum ultra-violet spectroscopic ellipsometry study of sputtered BeZnO thin films

Optik ◽  
2011 ◽  
Vol 122 (22) ◽  
pp. 2050-2054 ◽  
Author(s):  
Jebreel M. Khoshman ◽  
Martin E. Kordesch
Keyword(s):  
Thin Films ◽  
Spectroscopic Ellipsometry ◽  
Ultra Violet ◽  
Vacuum Ultra Violet

Control of a Robotic UV Curing Process With Thermal Vision Feedback Through Two IR Cameras

2009 ◽  
Author(s):  
Fan Zeng ◽  
Beshah Ayalew ◽  
Mohammed Omar
Keyword(s):  
Control Variable ◽  
Ultra Violet ◽  
Uv Curing ◽  
High Energy ◽  
Curing Process ◽  
Radiant Intensity ◽  
Loop Control ◽  
Thermal Vision ◽  
Uv Curing Process ◽  
Vision Feedback

Robotic ultra-violet (UV) curing is considered to be one of the effective ways to replace the current convection-based methods in various manufacturing processes due to its fast curing rate and high energy efficiency. This paper presents a closed-loop control of a robotic UV curing system by using thermal vision feedback through two infrared (IR) cameras. The proposed approach is developed based on a mathematical analysis of the fundamental UV curing process and the integration of the local and global IR cameras in a cascade manner. A computer simulation study is conducted to evaluate the proposed strategy by regarding two control variables: the radiant intensity of the UV heater and the sweeping speed of the robot end effector. The results indicate that controllers using either control variable can compensate for interferences and improve curing quality under this thermal-vision-based architecture.

scholarly journals Luminescence in KI:Tl

1961 ◽  
Vol 14 (3) ◽  
pp. 368 ◽  
Author(s):  
JE Alderson ◽  
SE Williams
Keyword(s):  
Single Crystals ◽  
High Energy ◽  
Activator Concentration ◽  
Host Crystal ◽  
Absorption Bands ◽  
High Energy Side ◽  
Luminescence Efficiency ◽  
Vacuum Monochromator ◽  
Impurity Centre ◽  
Energy Side

Freshly cleaved single crystals of KI:TI containing various concentrations of Tl have been irradiated in a vacuum monochromator in the 2800-1100 A region at temper. atures between -140 and 45 �0. The relative luminescence efficiencies in the Tl absorption bands and the host crystal fundamental absorption show that energy is transferred from host crystal to impurity centre to produce luminescence at room temperatures. To the high energy side of a threshold, which appears to depend on activator concentration, the luminescence efficiency is superlinear above about 15 �0 for KI:Tl (0�0005%).

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