Doping and Polar Interface-Induced High-Position Sensing in the PEDOT:PSS/Si Heterojunction and Its Multifunctional...

Area of Science:

• Optoelectronics
• Materials Science
• Semiconductor Devices

Background:

• Position-sensitive detectors (PSDs) are crucial for optical imaging.
• Enhancing the sensitivity and tunability of PSDs remains an active research area.
• PEDOT:PSS/Si heterojunctions offer potential for novel photodetector applications.

Purpose of the Study:

• To develop a highly sensitive, self-powered position-sensitive detector (PSD) based on a PEDOT:PSS/Si heterojunction.
• To investigate the effects of doping and pyroelectric phenomena on PSD performance.
• To demonstrate a high-resolution optical imaging system utilizing the developed PSD.

Main Methods:

• Fabrication of a PEDOT:PSS/Si heterojunction device.
• Optimization of band structure using FS-300 additive doping.
• Characterization of lateral photovoltaic response and pyroelectric effect under pulsed illumination.
• Design and testing of an optical imaging system.

Main Results:

• Doping significantly enhanced the built-in electric field, increasing open-circuit voltage to 0.45 V and position sensitivity to 404.6 mV/mm.
• A pyroelectric field induced by polar symmetry at the interface boosted position sensitivity by 192.5% to 778.8 mV/mm.
• The PSD demonstrated tunable performance across electrode spacings (0.5–9 mm), maintaining 170 mV/mm sensitivity at 9 mm, enabling adjustable imaging resolution.

Conclusions:

• The developed PEDOT:PSS/Si PSD offers high sensitivity and self-powered operation.
• Pyroelectric enhancement and tunable electrode spacing provide versatile capabilities for optical imaging.
• This technology holds promise for advanced optoelectronic applications requiring high-resolution imaging.