Sb2Se3/p-Si position-sensitive detector has high sensitivity and fast response

Jan. 1, 2019
A lateral-effect position-sensitive detector (PSD) based on an antimony selenide/silicon (Sb2Se3/p-Si) junction shows a position sensitivity of up to 448 mV/mm for visible/near-IR light.

Lateral-effect position-sensitive detectors (PSDs) are an essential component of many laser-optical systems, especially those that require some sort of beam alignment (quad-cell PSDs, which operate on a different principle, are also important). Researchers at the Harbin Institute of Technology (Harbin, China) have demonstrated PSDs using antimony selenide/silicon (Sb2Se3/p-Si) junctions fabricated using pulsed laser deposition (PLD) that exhibit a large lateral photovoltaic (LPV) effect that is linear with laser spot position with a maximum position sensitivity of up to 448 mV/mm and an optical relaxation time (1/e) for the LPV effect of 4.98 μs. Tested at light with wavelengths of 635, 780, and 808 nm, the high LPV and rectifying behavior of the room-temperature device makes it a promising candidate for many general-purpose applications in optoelectronics, say the researchers.

Sb2Se3 films with a thickness of 108 nm were deposited on three separate Si substrates with resistivity ranges of 500–100, 8–12, and 0.1–1 Ω·cm, respectively. The highest position sensitivity of 448 mV/mm was seen for a Si resistivity of about 8 to 12 Ω·cm. LPV data as a function of laser power from 1 to 40 mW was taken for the three test wavelengths, showing that the LPV saturates rapidly with laser power—at about 1 mW or so in the case of light at 635 nm. Reference: Y. Zhang et al., Opt. Express (2018); https://doi.org/10.1364/oe.26.034214.

About the Author

John Wallace | Senior Technical Editor (1998-2022)

John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.

Sponsored Recommendations

Download New Product Development Strategies White Paper

March 27, 2025
Discover the importance of new product innovation, different process methods, and best practices for optimizing your company’s strengths.

Manufacturing Considerations for Tolerancing Aspheres

March 13, 2025
Understand the critical factors in manufacturing aspheres and how Lacroix Optics ensures precise tolerancing in every optical component.

Explore Our Videos: Insights into Precision Optics

March 13, 2025
Get an inside look at Lacroix Optics with our collection of informative videos showcasing our capabilities, innovations, and processes.

Optical Assemblies: Reliable and Precise Solutions

March 13, 2025
Ensure your optical system works seamlessly with Lacroix Optics' custom optical assemblies. Discover the precision and reliability we bring to every project.

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!