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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.

This study aims to investigate the effects of indium composition on surface morphology and optical properties of indium gallium nitride on gallium nitride (InGaN/GaN) heterostructures.

The InGaN/GaN heterostructures were grown on flat sapphire substrates using a metal-organic chemical vapour deposition reactor with a trimethylindium flow rate of 368  sccm. The indium composition of the InGaN epilayers was controlled by applying different substrate temperatures. The surface morphology and topography were observed using field emission scanning electron microscope (F.E.I. Nova NanoSEM 450) and atomic force microscopy (Bruker Dimension Edge) with a scanning area of 10 µm × 10 µm, respectively. The compositional analysis was done by Energy Dispersive X-Ray Analysis. Finally, the ultraviolet-visible (UV-Vis) spectrophotometer (Agilent Technology Cary Series UV-Vis-near-infrared spectrometer) was measured from 200 nm to 1500 nm to investigate the optical properties of the samples.

The InGaN/GaN thin films have been successfully grown at three different substrate temperatures. The indium composition reduced as the temperature increased. At 760 C, the highest indium composition was obtained, 21.17%. This result was acquired from the simulation fitting of ω−2θ scan on (0002) plane using LEPTOS software by Bruker D8 Discover. The InGaN/GaN shows significantly different surface morphologies and topographies as the indium composition increases. The thickness of InGaN epilayers of the structure was ∼300 nm estimated from the field emission scanning electron microscopy. The energy bandgap of the InGaN was 2.54 eV – 2.79 eV measured by UV-Vis measurements.

It can be seen from this work that changes in substrate temperature can affect the indium composition. From all the results obtained, this work can be helpful towards efficiency improvement in solar cell applications.

The purpose of this paper is to investigate the effect of growth temperature on the evolution of indium incorporation and the growth process of InGaN/GaN heterostructures.

To examine this effect, the InGaN/GaN heterostructures were grown using Taiyo Nippon Sanso Corporation metal-organic chemical vapor deposition (MOCVD) SR4000-HT system. The InGaN/GaN heterostructures were epitaxially grown on 3.4 µm undoped-GaN (ud-GaN) and GaN nucleation layer, respectively, over a commercial 2” c-plane flat sapphire substrate. The InGaN layers were grown at different temperature settings ranging from 860°C to 820°C in a step of 20°C. The details of structural, surface morphology and optical properties were investigated using X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), atomic force microscopy and ultraviolet-visible (UV-Vis) spectrophotometer, respectively.

InGaN/GaN heterostructure with indium composition up to 10.9% has been successfully grown using the MOCVD technique without any phase separation detected within the sensitivity of the instrument. Indium compositions were estimated through simulation fitting of the XRD curve and calculation of Vegard’s law from UV-Vis measurement. The thickness of the structures was determined using the Swanepoel method and the FE-SEM cross-section image.

This paper report on the effect of MOCVD growth temperature on the growth process of InGaN/GaN heterostructure, which is of interest in solid-state lighting technology, especially in light-emitting diodes and solar cell application.

This paper aims to explore the level of hibah knowledge among Muslims in Kedah and investigate its determinants, consisting of education level, education stream, religiosity, social influence and social media.

This study is quantitative in nature. Questionnaires were distributed to collect data from Muslims in Alor Setar, Kedah. In total, 195 questionnaires were collected and data were analyzed using descriptive analysis, correlation analysis and multiple regression analysis.

The study finds that Muslims in Alor Setar, Kedah have good knowledge of hibah. Further, education stream, religiosity, social influence and social media were identified as significant factors that influence their knowledge of hibah.

The first limitation is its narrow focus in surveying Muslims only in Alor Setar, Kedah. The second limitation is the limited number of determinants used in investigating hibah knowledge among Muslims and the techniques used in analyzing the data. Despite these limitations, the study’s findings provide invaluable insights into the factors influencing hibah knowledge among Muslims in Alor Setar, Kedah.

This study provides insights regarding the significant personal factors and environmental factors to increase Muslims’ knowledge of hibah. The link between the Islamic education stream and hibah knowledge provides a clear indication that Islamic education can curb the economic problems caused by the substantial amounts of frozen and unclaimed assets in Malaysia. A significant relationship between the environmental factors (social influence and social media) and hibah knowledge also implies that the government and private agencies related to Islamic estate planning and management may use these significant determinants as part of the marketing strategy to increase the usage of hibah as an alternative tool for estate planning.

This study contributes to a better understanding of Muslims’ knowledge about hibah. The government and related agencies in Islamic estate planning and management can now gain better insights into Muslims’ level of knowledge about hibah and the factors influencing their knowledge of hibah as an effective tool for Islamic estate planning and management. Hence, more effective strategies can be recommended to enhance the knowledge of Muslims on hibah. The findings of this study should be of value to the government in its effort to address the increasing number of frozen estates in Malaysia.

This paper aims to attempt to present a number of higher purposes of Islamic law that include within their scope the preservation and protection of the natural environment. Such preservation is in the best interest of mankind.

The researchers have extrapolated evidence from the Qur’an and authentic traditions of the Prophet (PBUH) that afford a sense of certainty that Islamic laws contain operative or effective causes (illa) seeking the welfare of human beings and society.

The Qur’an and Sunnah have placed great importance on the preservation and protection of the environment. They have extolled the merits of treating the environment with care and compassion. Evidence of this can be found in authentic hadiths beginning with the Book of Purity and is found in many of the teachings concerning worship rituals and civic activities.

The researchers have attempted to present a number of higher purposes of Islamic law that include within their scope the preservation and protection of the natural environment. Such preservation is in the best interest of mankind. For this, the researchers have extrapolated evidence from the Qur’an and authentic traditions of the Prophet (PBUH) that afford a sense of certainty that Islamic laws contain operative or effective causes (illa) seeking the welfare of human beings and society.

This study aims to systematically review the literature on modern Islamic finance transactions pertaining to Gharar dimensions. Gharar is defined as uncertainty that potentially leads to ambiguities and conflicts in contracts.

The articles reviewed in this study consisted of 13 articles related to Gharar published between 2013 and 2022. All selected articles were empirically and descriptively searched using specific keywords and strings. The main sources for this study were Scopus and Web of Science (WoS), whereas Google Scholar was a supportive database.

The review found that the dimensions that discussed previous research were trying their best to elaborating Gharar in modern financial transactions. They also demonstrate that rigorous study and deployment of the definition remain in the context defined by jurisprudence scholars. The focus of recent studies pertaining to Gharar is derivatives products that indicate high possibility of uncertainty in its operation.

This method relies heavily on the accessed database, namely, Scopus and WoS, also referred to the articles as recommended by the databases. Furthermore, the criteria of inclusion and exclusion of papers outlined by the authors deemed as an intrinsic limitation in writing systematic literature review.

To the best of the authors’ knowledge, this paper is original in its nature whereby the scholars had different comprehension on how Gharar exists in transaction but they still centred in its original meaning of uncertainty. As a result, this paper also realized how Gharar were interpreted differently relied on the contract’s nature and behaviour. In addition, this paper is expected to contribute to understand how Gharar been interpreted in modern finance transactions and finally reached to the point that further research is needed in establishing Gharar parameter for each contract in Islamic commercial law.

This paper aims to present the viability of unit trust waqf (Islamic endowment) as an alternative asset class for waqf creation.

This paper starts with the conceptual exploration of the literature in the areas of waqf. The sources of the literature cover authentic sources of the Qurʾān and ḥadīth, as well as secondary sources such as books, journal articles and online resources.

This paper provides the conceptual framework of five models of unit trust waqf and their investment management parameters.

The novelty of this paper lies in its attempt to highlight the importance of waqf investment strategy in ensuring sustainable returns for waqf. It does so by introducing the conceptual models of unit trust waqf as viable mechanisms to pool more cash waqf from individual investors. The sustainability of the capital waqf assets in the form of unit trusts is maintained through the parameters for its application proposed towards the end of the paper.

The paper aims to examine the determinants of corporate social responsibility (CSR) disclosures in the annual reports of Malaysian public listed companies (PLCs). In 2006, Bursa Malaysia Berhad (BMB) launched its CSR Framework (effective in 2007) which is supposed to guide the Malaysian PLCs’ CSR disclosures. It is believed that this CSR framework may influence CSR disclosures to be more systematic, yet there is no evidence whether this framework influences the extent and quality of CSR disclosures. Thus, this study examines this area of research. The study also tests the influence of award on CSR disclosures.

CSR disclosure checklist was developed to analyse the extent and quality of CSR information disclosures in the year 2008 annual reports of the Malaysian PLCs.

Malaysian PLCs disclose more CSR information related to community and environment than workplace and marketplace CSR themes. On the other hand, the quality of disclosure practices was minimal when it is compared to the extent of disclosure practices. Finally, the study also found that the award’s variable has a significant positive relationship with both the extent and quality of CSR disclosure practices of the Malaysian PLCs.

The recently developed BMB’s CSR framework seems to have impact on the level and systematic CSR reporting practices of Malaysian PLCs. However, the quality of CSR disclosures is considered minimal.

The results of the study bring some practical implications to the regulators, particularly Bursa Malaysia. First, it is good to observe that most companies have practiced specific disclosure in a separate statement with regard to CSR. However, the format of presentation and the extent of disclosure vary among the firms. Second, further guidelines need to be developed to provide a clearer framework of disclosure for CSR information. At the moment, Bursa Malaysia only listed down general principles of CSR themes. In addition, the regulators should also look into the evolving issues in CSR, such as the issue of climate change reporting. For example, the Climate Disclosure Standards Board has issued a voluntary Climate Change Reporting Framework.

This study examined both the traditional (i.e. firm size and profitability) and non-traditional (i.e. award) factors influencing management’s decision to disclose CSR information in the annual reports of the Malaysian PLCs. Furthermore, the study reported how Malaysian PLCs comply with the recently implemented CSR framework issued by BMB.

Islamic finance and Halal product sectors are thriving successfully. This chapter is a general review of the perception of Asian consumers on Islamic finance and Halal sectors in the global Halal economy.

The first section will briefly describe the Halal concept in both Islamic finance and Halal industries, and the growth of both sectors in Asian countries. The second part highlights the review of Asian consumers’ perception towards Islamic finance products and Halal products.

The review found that the consumers’ perception towards the Islamic finance products and Halal products is distinctive. This is due to the diversity of Asian countries in terms of geography, religion, culture, ethnic, school of thoughts (madzahib), income per capita and government’s involvement.

The third part of the chapter concentrates on planning towards Halal marketing, which involves the move and future challenges in different layers of industries to gear up and strengthen the Halal economy.