Scientists from the University of the Philippines (UP) have achieved a breakthrough that could make advanced technology more accessible. A new semiconductor structure has been developed by scientists from the University of the Philippines–Diliman College of Science (UPD-CS). This innovation promises to lower the cost of terahertz (THz) antenna devices. THz technology has applications in medicine and high-speed wireless communication.
The goal of the THz research is to make THz-Time Domain Spectroscopy (THz-TDS) widely usable. This invention addresses key technical and economic barriers to its adoption.
Dr. Cyril Salang, from the UPD-CS Materials Science and Engineering Program (MSEP), led the team. The team includes Dr. Arnel Salvador, Dr. Armando Somintac, and Dr. Elmer Estacio of the UPD-CS National Institute of Physics (NIP). Also included is Dr. Joselito Muldera of RIKEN, a research institute in Japan. They created a new semiconductor component design with a substrate, a buffer layer, and an epitaxial layer. The epitaxial layer is a thin crystal layer grown on top.
The unique aspect is the mismatched buffer layer. Its atomic structure differs significantly from the substrate and the epitaxial layer. Mismatches usually cause defects, but this invention results in high-quality layers. These layers perform as well as, or even better than, traditional materials in THz emitters.
The team added a growth-interrupted region and a superlattice. The superlattice is a structure that strengthens the adhesion between components. The p-type indium arsenide (p-InAs) layer was grown on a superlattice. This was placed on a buffer layer, over a growth-interrupted region, on a gallium antimonide (n-GaSb) substrate. The invention delivered impressive results when tested.
The performance was comparable to traditional materials with a 0.80 μm laser. It performed even better with a 1.55 μm fiber laser, which is cheaper. This makes the invention a potential game-changer for THz-TDS systems.
Dr. Salang shared the journey of the invention. “My paper was published in 2015, followed by an invention disclosure later that year. With support from the UP Diliman Office of the Vice Chancellor for Research and Development (OVCRD), the patent application was filed in February 2016 and was officially granted in 2024,” she said.
Dr. Salang also stated the importance of the patent. “Receiving a national patent means that the originality of our work is recognized. It encourages me to do further innovation,” she added.
With this patent, Dr. Salang and her team can contribute more to the terahertz industry.
