Prof. Dr. Wan Haliza Binti Abd Majid
Professor
Faculty of Science
Universiti Malaya
q3haliza@um.edu.my

NO	NAME	PROJECT TITLE	RESEARCH DOMAIN (SUB DOMAIN)
1	Prof. Dr. Wan Haliza Binti Abd Majid	Gallium Nitride Epitaxy for Power and Optoelectronic Devices	Pure and Applied Science (Materials Science)
2	Prof. Dr. Zainuriah Hassan	Energy Efficient Lighting	Pure and Applied Science (Materials Science)
3	Prof. Dr. Prabakaran A/L Poopalan	GaN LED Graded Encapsulant Refractive Index for Optical Impedance Matching	Pure and Applied Science (Physics)
4	Prof. Dr. Ainin Binti Sulaiman	Socio Economic Impacts of Light-Emitting Diode (LED) Lighting Usage in Malaysia	Social Sciences (Management [Organisational Behaviour, Entrepreneurship])

3 years (15 October 2017 – 15 October 2020)

Nitride-based wide-bandgap compound semiconductors, such as gallium nitride (GaN) and its tertiary and quaternary alloys are very promising materials for fabrication of new-generation energy-efficient optoelectronic and power devices. Nitride-based compound semiconductors have large tunable direct bandgap range from 0.7 eV for indium nitride (InN) to 6.2 eV for aluminum nitride (AlN), allowing for the fabrication of high-performance optoelectronic emission and sensing devices in the ultra-violet, visible, and infrared spectral range. Additionally, 2-dimensional electron gas (2DEG) at aluminum gallium nitride (AlGaN) / gallium nitride (GaN) interlayer works similar to channel region in typical metal-oxide semiconductor (MOS) transistors, allowing for the fabrication of high-electron mobility transistor (HEMT), which excels in terms of carrier mobility, operating temperature and operating voltage over conventional silicon (Si) - based transistors. The most common techniques for the epitaxial growth of GaN are hydride vapor phase epitaxy (HVPE) and metal-organic chemical vapor deposition (MOCVD). HVPE allows fast epitaxial growth with 100-300 µm/hour growth speed that makes it suitable to grow thick/bulk layer for GaN templates and substrates. Meanwhile, MOCVD allows precise epitaxial growth with 1-3 µm/hour growth speed which is suitable for device-grade nanometer-scale single-crystalline thin-film epitaxy. Further arrangement of the multi-layered thin-films enable the realization of optoelectronic devices such as LED and HEMT. LED is applicable in energy-efficient lighting, while HEMT has tremendous potential for applications in power electronics, such as power factor correction (PFC) circuits in power adapters as well as inverters in hybrid vehicles. The current white LED lighting is based on phosphor conversion of blue LEDs, which has limited efficiency, high cost, and insufficient illumination quality. By mixing highly efficient LEDs of red, green and blue (RGB) colors to form white light, there will be huge potential for efficiency improvement with much better illumination quality. The key to successful color mixing for white light is to enhance the efficiency of LEDs in the long wavelength range, specifically the green LEDs. Theoretically, the emission spectra of the AlGaInN system cover the entire range of visible light. The AlGaInN system has shown its strength in blue light — the highest external quantum efficiency (EQE) goes beyond 80% for GaN based blue LEDs. They also have advantages in the green light range: 30% EQE is much higher than that of the conventional AlGaInP green LEDs. However, it still has great potential compared with blue LEDs. The efficiencies of AlGaInN-based LEDs drop fast as wavelength increases from 450 nm to 550 nm, and the efficiencies of AlGaInP-based LEDs drop even faster as wavelength decreases from 650 nm to 600 nm. The efficiencies of LEDs are relatively low within the range from 500 nm to 600 nm, which is known as the “green gap.” The peak of the CIE eye sensitivity function curve lies just in the center of the gap, implying low efficiencies for the sensitive colors. The purpose of developing GaN-based green LEDs is not only to increase the luminous efficiency of LEDs, but also to fill a blank emission region of visible light for solid state lighting. This research project proposes fundamental development in 2 types of devices, namely high-electron mobility transistor (HEMT), and light-emitting diode (LED) as part of optoelectronic device development. Research on HEMT focuses on GaN-based thin-film epitaxy on silicon substrate using MOCVD, and (iii) epitaxy and fabrication of GaN-based HEMT power device utilising silicon substrates. Meanwhile, research on LED focuses on (i) the optimization and investigation of growth techniques to obtain efficient green-emission InGaN-based multi-quantum well, and (ii) demonstration and further optimizations of green LED grown on patterned sapphire substrate (PSS).

1. To explore the advanced epitaxy and fabrication technique for realization of gallium nitride-based power devices.
2. To study, optimize and develop a novel gallium nitride-based light emitting diode.
3. To optimize and develop advanced packaging for high-brightness light-emitting diodes and power devices.
4. To study the social impact of light-emitting diode usage in Malaysia.

1. Talent:
   • 1 PHD
     1. Farina Saffa Binti Mohamad Samsamnun (Graduated)
     2. Omar Ayad Fadhil (Graduated)
     3. Husnen R. Abd (Graduated)
     4. Siti Nurfarhana Sohimee (Graduated)
     5. Mohd Ann Amirul Zulffiqal Md Sahar (Graduated)
     6. Shafouri Mahmood Shaikhan Ta Eeb (Graduated)
   • 1 Master
     1. Mohd Raqif Bin Mahat (Graduated)
     2. Noor Afifa Mohd Hanafiah (Graduated)
     3. Hasmaifarahatul Hidayah Abd Wahab (Graduated)
     4. Ahmad Sauffi Bin Yusof (Graduated)
2. Publication:
   
   • 62 Article in Indexed Journals
   • 17 Conference Proceedings
   • 1 Book Chapter
   • 1 Newspaper Article
3. Intellectual Property :
   • ● Patent : PCT/MY2019/00003
   • ● Patent : PCT/MY2019/00004
   • ● Patent : US2020/0411714 A1
   • ● Patent : PI 2017704381
   • ● Patent : PI2020001166
   • ● Patent : PI2021002404
   • ● Trademark : TM2019007531

1. This program strengthens the R&D capability (capacity and talent) in Malaysia for semiconductor wide band gap research. Several critical equipment for device characterizations have been procured to increase research capability and competitiveness and 36 have been trained in this research area.
2. Knowledge transfer and talent pipeline are created between academia and industry. The program trains and develops talent that can be employed by the industry to further uplift the industry capability and development in the future.
3. Via knowledge sharing, industries are able to create new products and services.
4. Attract foreign industry related for investment in Malaysia benefited academic, industry and the government
5. Society has the option of more environmentally-friendly, highly efficient, and reliable products.
6. The utilization of non-toxic end-products benefited the environment.