Research Topics / Interests

Research and development of novel and innovative SPAD devices/sensors

Development of novel back-illuminated (backside illumination; BSI) 3D-stacked SPAD sensors

Development of SPADs in standard advanced CMOS/HV CMOS/BiCMOS/BCD/SOI CMOS/CIS(CMOS image sensor)/3D CMOS technologies

Development of CMOS-compatible SiPMs

Investigation on SiGe/Si, Ge/Si, and InGaAs/InP SPADs

Investigation on SPAD characteristics at cryogenic temperatures

SPAD simulation and modeling
(TCAD, numerical, equivalent circuit)

LiDAR/ToF sensors & applications: ADAS (advanced driver assistance systems), eventually for autonomous vehicles, robots, drones, unmanned aerial vehicles (UAVs), submarine/airborne/satellite LiDAR, machine vision, industrial automation, etc. and mobile phones for 3D face/gesture recognition/tracking, depth imaging, biometric authentication, AR/VR/MR/XR (augmented/virtual/mixed/extended reality), etc.

Biomedical applications: TOF PET (time-of-flight positron emission tomography), X-ray, SPECT (single-photon emission computed tomography), FLIM (fluorescence-lifetime imaging microscopy), super-resolution microscopy, NIRI (near-infrared imaging), PCR (polymerase-chain-reaction), ELISA (enzyme-linked immunosorbent assay), etc.

Safety and security: Night vision, low-light imaging, security cameras, radiation detectors, gamma cameras, dosimeters, cargo scanners, environmental monitoring, etc.

Quantum applications: Integrated photonic quantum technology, Integrated photonic quantum detector, QKD (quantum key distribution), quantum communication, QRNG (quantum random number generators), quantum cryptography, optical quantum computing, etc.

More applications wherever single-photon sensitivity and high precision time-of-arrival detection are critical.

Optimization of CMOS-APDs (CMOS-compatible APDs) for each applications in terms of responsivity, bandwidth, and noise

Development of high-speed & high-responsivity photodetectors

Development of APDs in standard advanced CMOS/HV CMOS/
BiCMOS/BCD/SOI CMOS/CIS(CMOS image sensor)/3D CMOS technologies

Investigation on SiGe/Si, Ge/Si, and InGaAs/InP APDs

Nanomaterial(2D)-based PDs and APDs

PD/APD device simulation and modeling
(TCAD, numerical, equivalent circuit)

Indirect ToF/LiDAR sensors & systems: 3D face recognition (Face ID), gesture recognition and tracking, etc.

Optical-interconnect applications: rack-to-rack interconnects within data centers and computer clusters, chip-level interconnects, etc.

Vehicular networks/communications, home networks, etc.

FSO (free-space optical) communications: VLC (visible light communication), Li-Fi, etc.

Optoelectronic mixers & self-oscillating optoelectronic mixers and their applications

RoF (radio-over-fiber) systems and micro-/millimeter-wave fiber-wireless Systems

Biomedical applications wherever higher responsivity is needed.