A high-sensitivity SnSe/Si heterojunction position-sensitive detector for ultra-low power detection

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Position-sensitive detectors (PSDs) are vital for non-contact measurements but face limitations in spectral range and sensitivity.
• Existing PSDs struggle with broad light detection and require higher sensitivity for practical applications.

Purpose of the Study:

• To develop an ultra-sensitive SnSe/Si heterojunction device for improved position-sensitive detection.
• To enhance the spectral range and sensitivity of PSDs for wider applicability.

Main Methods:

• Fabrication of a SnSe/Si heterojunction using glancing-angle magnetron sputtering deposition.
• Growth of a large-area uniform SnSe nanorod array film on a silicon substrate.
• Characterization of the device's photoresponse, position sensitivity, and spectral sensitivity.

Main Results:

• The SnSe/Si PSD demonstrated an ultrahigh position sensitivity of 1517.4 mV mm⁻¹ and spectral sensitivity of 4 × 10⁴ V W⁻¹.
• The device exhibited excellent photoresponse across a wide spectral range (405-980 nm).
• A low detection limit power of 10 nW was achieved, highlighting its capability for weak light detection.

Conclusions:

• The SnSe/Si heterojunction shows significant promise as a material for ultrasensitive optical position-sensitive devices.
• The unique structural features and interface effects contribute to the remarkable performance of the fabricated PSD.
• This advancement opens new possibilities for applications requiring high-precision optical detection.