学术报告：Hydrogenated amorphous silicon platform for photonics
特邀学者：澳大利亚国立大学 Duk-Yong Choi 博士，高级研究员（副教授）
Senior fellow (associate professor), laser physics centre（LPC） in the Australian National University
Silicon photonics has become the dominant technology for integrated photonic devices. It supports low power consumption, dense integration with CMOS electronics, low cost and is, therefore, promising for high-performance communication and computing. Crystalline silicon (c-Si) has been the main platform which not only transports the light signals, but also incorporate light sources and detectors. High-quality c-Si, however, is impossible to grow on a foreign substrate, implying that it cannot be used for advanced multilayer photonic integration. Hydrogenated amorphous silicon (a-Si:H) is emerging as an alternative in this perspective. A distinct advantage of a-Si:H comes from the fact that it can be deposited easily at low temperature on almost any substrates, facilitating back-end integration of a-Si:H photonic components on top of pre-processed CMOS electronic chips without any damage to the underlying metal wires.
We have developed hydrogenated amorphous silicon (a-Si:H) for complementary or alternative platform for crystalline silicon in silicon photonics applications. Fully leveraging the unique features of a-Si:H we demonstrated vertically coupled microring resonator, highly angle tolerant colour filters, and micro-lens array in near infrared (IR) band. Recently, the material has been applied to dielectric meta-surfaces, new emerging research field; where we demonstrated silicon visible colour filters, meta-lens at mid IR, chemical sensors, and ultrafast optical switch.
Biography: Dr. Duk-Yong Choi is a senior fellow (associate professor) at the laser physics centre in the Australian National University. He has been a member of CUDOS (Centre for Ultra-High Bandwidth Devices in Optical System) program since 2005. In the program his role is to develop the fabrication process of nonlinear optic devices utilizing chalcogenide glass films and to study the structural, optical and electrical properties of the materials. Recently his research has extended to silicon photonics – Germanium laser & photo-detector, hydrogenated amorphous silicon. He got his PhD at 1998 from Materials science and engineering in Seoul national university in Korea, then worked at Samsung electronics for 6.5 years.