TY - JOUR

T1 - Polarized p–n junction Si photodetector enabled by direct laser-induced periodic surface structuring

AU - Borodaenko, Yulia

AU - Cherepakhin, Artem

AU - Gurbatov, Stanislav O.

AU - Modin, Evgeny

AU - Shevlyagin, Aleksandr V.

AU - Kuchmizhak, Aleksandr A.

PY - 2025/1/1

Y1 - 2025/1/1

N2 - Monocrystalline silicon (Si or c-Si) is of paramount importance for modern optoelectronics, yet its centrosymmetric crystal lattice restricts any inherent optical anisotropy. This fundamental limitation precludes construction of polarization-sensitive Si-based photodetectors (PD) relevant for bioimaging, information encryption and ellipsometry. In this work, we used laser-induced periodic surface structuring (LIPSS) to directly imprint optically anisotropic nanogratings with a periodicity around 270 nm over the active area of a vertical p–n junction Si PD. Sensitivity to polarization of the incident radiation was observed within 700–1100 nm spectral range with a photoresponse modulation up to 80% for the cross-polarized light under zero bias conditions. Defect-mediated absorption within laser-patterned layer was found to expand operation range of the PD rendering it with ability to detect photons with sub-band gap energies (up to 1400 nm), while causing no crucial degradation of dynamic characteristics and photoresponse of the self-powered device within common operation window. Under a small reverse bias of 1 V, the LIPSS-patterned PD provides cross-polarized photoresponse modulation up to 430% surpassing 100% external quantum efficiency benchmark under optimal excitation. Importantly, such competitive device performance was achieved through facile upscalable procedure without hyperdoping requiring expensive gas chambers and toxic chemicals.

AB - Monocrystalline silicon (Si or c-Si) is of paramount importance for modern optoelectronics, yet its centrosymmetric crystal lattice restricts any inherent optical anisotropy. This fundamental limitation precludes construction of polarization-sensitive Si-based photodetectors (PD) relevant for bioimaging, information encryption and ellipsometry. In this work, we used laser-induced periodic surface structuring (LIPSS) to directly imprint optically anisotropic nanogratings with a periodicity around 270 nm over the active area of a vertical p–n junction Si PD. Sensitivity to polarization of the incident radiation was observed within 700–1100 nm spectral range with a photoresponse modulation up to 80% for the cross-polarized light under zero bias conditions. Defect-mediated absorption within laser-patterned layer was found to expand operation range of the PD rendering it with ability to detect photons with sub-band gap energies (up to 1400 nm), while causing no crucial degradation of dynamic characteristics and photoresponse of the self-powered device within common operation window. Under a small reverse bias of 1 V, the LIPSS-patterned PD provides cross-polarized photoresponse modulation up to 430% surpassing 100% external quantum efficiency benchmark under optimal excitation. Importantly, such competitive device performance was achieved through facile upscalable procedure without hyperdoping requiring expensive gas chambers and toxic chemicals.

KW - Femtosecond lasers

KW - Laser-induced periodic surface structures

KW - Polarization-sensitive photoresponse

KW - Silicon

KW - p–n junction photodetector

UR - https://www.mendeley.com/catalogue/92e027a3-842d-3c5e-b025-5b6d04d65df0/

U2 - 10.1016/j.surfin.2024.105568

DO - 10.1016/j.surfin.2024.105568

M3 - Article

VL - 56

JO - Surfaces and Interfaces

JF - Surfaces and Interfaces

SN - 2468-0230

M1 - 105568

ER -