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Due to rapid technological evolution driven by display manufacturers, the television (TV) market of flat panel displays has been fast growing with the advancement of digital technologies in broadcasting service. Recently, organic light-emitting diode (OLED) successfully penetrated into the large-size TV market, catching up with light-emitting diode (LED)-liquid-crystal display (LCD). This paper aims to investigate the market penetration of OLED technologies by determining their technology adoption rates based on a diffusion model.

Through the rapid evolution of information and communication technology, as well as a flood of data from diverse sources such as research awards, journals, patents, business press, newspaper and Internet social media, data mining, text mining, tech mining and database tomography have become practical techniques for assisting the forecaster to identify early signs of technological change. The information extracted from a variety of sources can be used in a technology diffusion model, such as Fisher-Pry where emerging technologies supplant older ones. This paper uses a comparison-based prediction method to forecast the adoption and diffusion of next-generation OLED technologies by mining journal and patent databases.

In recent years, there has been a drastic reduction of patents related to LCD technologies, which suggests that next-generation OLED technology is penetrating the TV market. A strong industry adoption for OLED has been found. A high level of maturity is expected by 2026.

For OLED technologies that are closely tied to industrial applications such as electronic display devices, it may be better to use more industry-oriented data mining, such as patents, market data, trade shows, number of companies or startups, etc. The Fisher-Pry model does not address the level of sales for each technology. Therefore, the comparison between the Bass model and the Fisher-Pry model would be useful to investigate the market trends of OLED TVs further. Another step for forecasting could include using industry experts and a Delphi model for forecasting (and further validation).

Fisher-Pry growth curves for journal publications and patents follow the expected sequence. Specially, journal publications and patents growth curves are close for OLED technologies, indicating a strong industry adoption.

An integration algorithm for effective and accurate integration of the Fourier—Bessel integral temperature solution of a five‐layer structure with a circular embedded source is reported. The circular source solution has the form of a single integration rather than the double integration of a solution for the structure with a rectangular source. Using the circular source solution, the computation time for temperature calculation is reduced by a factor of 10 compared with the rectangular source solution. To reduce the computation time further, this integration algorithm transforms the single integration into a fast‐converging simple summation. The effectiveness of this algorithm is most evident when the point of calculation is far from the source. Based on the solution and algorithm, a software program PAMICE has been written. An important application for the solution and integration algorithm is the use of a circular source instead of a square one as unit source to produce the unit thermal profile for real‐time thermal design of integrated circuits having large number of sources. The solution is also valuable for the thermal study and analysis of devices having circular sources such as power transistors and light emitting diodes. The algorithm can be applied to other similar solutions arising from structures with circular sources.

Motivated with the ever growing number of bibliometric trend extrapolation studies, the purpose of this paper is to demonstrate through two technologies how the selection of an upper limit of growth affects the correlation and causality of technology development measured with bibliometric data.

The paper uses Gompertz and Fisher-Pry curves to model the technological development of white light emitting diodes and flash memory, and show with extrapolation results from several bibliometric sources how a typical bias is caused in trend extrapolations.

The paper shows how drastic an effect the decision to set an upper bound has on trend extrapolations, to be used as a reference for applications. The paper recommends carefully examining the interconnection of actual development and bibliometric activity.

Despite increasing interest in modelling technological data using this method, reports rarely discuss basic assumptions and their effects on outcomes. Since trend extrapolations are applied more widely in different disciplines, the basic limitations of methods should be explicitly expressed.

The aims of this paper is to study the effects of the V/III ratio of indium gallium nitride (InGaN) quantum wells (QWs) on the structural, optical and electrical properties of near-ultraviolet light-emitting diode (NUV-LED).

InGaN-based NUV-LED is successfully grown on the c-plane patterned sapphire substrate at atmospheric pressure using metal organic chemical vapor deposition.

The indium composition and thickness of InGaN QWs increased as the V/III ratio increased from 20871 to 11824, according to high-resolution X-ray diffraction. The V/III ratio was also found to have an important effect on the surface morphology of the InGaN QWs and thus the surface morphology of the subsequent layers. Apart from that, the electroluminescence measurement revealed that the V/III ratio had a major impact on the light output power (LOP) and the emission peak wavelength of the NUV-LED. The LOP increased by up to 53% at 100 mA, and the emission peak wavelength of the NUV-LED changed to a longer wavelength as the V/III ratio decreased from 20871 to 11824.

This study discovered a relation between the V/III ratio and the properties of QWs, which resulted in the LOP enhancement of the NUV-LED. High TMIn flow rates, which produced a low V/III ratio, contribute to the increased LOP of NUV-LED.

The purpose of this paper is to enhance the efficiency of the LED by introducing three-step magnesium (Mg) doping profile. Attention was paid to the effects of the Mg doping concentration of the first p-GaN layer (i.e. layer close to the active region). Attention was paid to the effects of the Mg doping concentration of the first p-GaN layer (i.e. layer close to the active region).

Indium gallium nitride (InGaN)–based light-emitting diode (LED) was grown on a 4-inch c-plane patterned sapphire substrate using metal organic chemical vapor deposition. The Cp₂Mg flow rates for the second and third p-GaN layers were set at 50 sccm and 325 sccm, respectively. For the first p-GaN layer, the Cp₂Mg flow rate varied from 150 sccm to 300 sccm to achieve different Mg dopant concentrations.

The full width at half maximum (FWHM) for the GaN (102) plane increases with increasing Cp₂Mg flow rate. FWHM for the sample with 150, 250 and 300 sccm Cp₂Mg flow rates was 233 arcsec, 236 arcsec and 245 arcsec, respectively. This result indicates that the edge and mixed dislocations in the p-GaN layer were increased with increasing Cp₂Mg flow rate. Atomic force microscopy (AFM) results reveal that the sample grown with 300 sccm exhibits the highest surface roughness, followed by 150 sccm and 250 sccm. The surface roughness of these samples is 2.40 nm, 2.12 nm and 2.08 nm, respectively. Simultaneously, the photoluminescence (PL) spectrum of the 250 sccm sample shows the highest band edge intensity over the yellow band ratio compared to that of other samples. The light output power measurements found that the sample with 250 sccm exhibits high output power because of sufficient hole injection toward the active region.

Through this study, the three steps of the Mg profile on the p-GaN layer were proposed to show high-efficiency InGaN-based LED. The optimal Mg concentration was studied on the first p-GaN layer (i.e. layer close to active region) to improve the LED performance by varying the Cp₂Mg flow rate. This finding was in line with the result of PL and AFM results when the samples with 250 sccm have the highest Mg acceptor and good surface quality of the p-GaN layer. It can be deduced that the first p-GaN layer doping has a significant effect on the crystalline quality, surface roughness and light emission properties of the LED epi structure.

The purpose of this paper is to model and analyze energy transfer through near‐field resonant coupling for high power light‐emitting diode (HPLED) illumination, with the intention to increase the appreciation and use of the coupled mode theory (CMT) other than the usual equivalent circuit method.

The CMT is extensively used to analyze the wireless energy transfer system because of its generality, simplicity, accuracy and intuitive understanding of near‐field resonant energy coupling mechanism.

The CMT forms a general way to model and analyze the non‐radiative magnetic resonant coupling systems. It is suitable not only for low frequency coupling but also for high frequency (of million‐Hertz) in which the circuit parameters are not easily obtained. Optimal coupling condition corresponding to the maximum power transfer is identified based on the CMT, and the multiple limit cycle phenomenon caused by the nonlinear nature of the HPLED is also described on the CMT model.

This paper takes advantages of CMT, i.e. generality, simplicity, accuracy and intuitive understanding to analyze the near‐field resonant energy coupling system. Key characteristics of the systems are explored based on the CMT, not the usual equivalent circuit method. The influence of nonlinear nature of the high power LED on energy transfer is also investigated. This work seeks a more general way than conventional equivalent circuit method to model and analyze the resonant magnetic system and the results obtained could facilitate better understanding of the resonant magnetic coupling mechanism and optimal design of the near‐field energy transfer system.

Polymeric nanocomposite films from PEDOT and MEH-PPV embedded with surface modified TiO₂ nanoparticles were prepared, respectively for the hole transport layer (HTL) and emission layer (EL) in Organic Light Emitting Diodes (OLED). The composite of MEH-PPV + nc-TiO₂ was used for Organic Solar Cells (OCS). The results from the characterization of the properties of the nanocomposites and devices showed that electrical (I-V characteristics) and spectroscopic (photoluminescent) properties of the conjugate polymers were enhanced due to the incorporation of nc-TiO₂ in the polymers. The OLEDs made from the nanocomposite films would exhibit a larger photonic efficiency and a longer lasting life. For the OSC made from MEH-PPV + nc-TiO₂ composite, the fill factor (FF) reached a value as high as 0.34. Under illumination of light with a power density of 50 mW/cm², the photoelectrical conversion efficiency (PEC) was found to be of 0.15% corresponding to an open circuit voltage V_OC = 1.15 V and a short-cut circuit current density J_SC = 0.125 mA/cm².

The purpose of this paper is to find an effective route to fabricate high transparent top electrode in quantum dots light-emitting diodes (QLEDs).

Al-doped ZnO (AZO) top cathode with high transparency have been deposited by an atomic layer deposition (ALD) method at 140°C for 1 h. The products are studied by UV-vis spectrometer and atomic force microscopy (AFM). The electroluminescence spectra of QLED are recorded using an Ocean Optics high-resolution spectrometer (HR4000). The devices were measured under ambient conditions without encapsulation.

The AZO-based QLED shows excellent performance with high luminance and current efficiency.

The AZO obtained by ALD method is a promising cathode candidate for application in QLEDs.