Current single-photon (SP) and photon-number-counting (PNC) detectors face limitations: superconducting detectors (SDs) require cryogenic cooling, while avalanche photodiodes (APDs) suffer from lower efficiency compared to SDs, high bias voltage, and avalanche noise. This project proposes a graphene-based photodetector integrating interfacial photogating with electron multiplication, aiming for high gain, faster response, and lower noise equivalent power (NEP)—a significant advancement in quantum photodetection.
Graphene-based photo-field-effect transistors (photo-FETs) offer ultrafast response, high carrier mobility, and room-temperature operation, making them a strong alternative to conventional detectors. However, current graphene/h-BN photodetectors rely on exfoliation or chemical vapor deposition (CVD) with transfer steps, introducing defects and contaminants. To address this, we will implement direct growth of graphene and hexagonal boron nitride (h-BN) layers via plasma-enhanced chemical vapor deposition (PECVD), ensuring a scalable, CMOS-compatible fabrication process that enhances material quality and device performance.
This research will focus on fabricating and studying graphene-based photo-FETs integrated with h-BN for enhanced low-light detection at room temperature. The project will explore the feasibility of single-photon sensitivity and photon-number resolution by optimizing photogating effects and leveraging electron multiplication for enhanced performance. Project objectives are: 1) Develop and study graphene/h-BN photo-FETs fabricated using direct PECVD synthesis; 2) Investigate the impact of h-BN encapsulation on photodetector responsivity, efficiency, gain and carrier transport; 3) Develop, fabricate, and study a graphene-based electron multiplication stage to achieve higher gain; 4) Integrate the newly-developed electron multiplication stage into the optimized graphene photo-FET and evaluate its photoresponse, gain, and detection efficiency.
Project funding:
Research Council of Lithuania, Designated Programme “Information technologies for the development of science and knowledge society”
Project results:
Projektas ką tik prasidėjo.
Period of project implementation: 2025-10-01 - 2027-08-31
Project coordinator: Kaunas University of Technology
