US 12,272,718 B2
Infrared detector improved via engineering of the effective mass of charge carriers
Axel Evirgen, Palaiseau (FR); Jean-Luc Reverchon, Palaiseau (FR); and Virginie Trinite, Palaiseau (FR)
Assigned to LYNRED, Palaiseau (FR); and COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, Paris (FR)
Appl. No. 18/275,174
Filed by LYNRED, Palaiseau (FR); and COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, Paris (FR)
PCT Filed Feb. 1, 2022, PCT No. PCT/EP2022/052347
§ 371(c)(1), (2) Date Jul. 31, 2023,
PCT Pub. No. WO2022/167419, PCT Pub. Date Aug. 11, 2022.
Claims priority of application No. 2101135 (FR), filed on Feb. 5, 2021.
Prior Publication US 2024/0136384 A1, Apr. 25, 2024
Prior Publication US 2024/0234473 A9, Jul. 11, 2024
Int. Cl. H01L 31/0304 (2006.01); H01L 27/146 (2006.01); H01L 31/0352 (2006.01)
CPC H01L 27/14649 (2013.01) [H01L 31/03046 (2013.01); H01L 31/035236 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A device (D1) for detecting infrared radiation, comprising at least one pixel (Pxl) having an axis (Δ) in a direction Z, said pixel comprising a first absorbent planar structure (SPA) comprising at least one semiconductor layer (Cmm, C1, C2);
each layer (Cmm, C1, C2) of the first absorbent planar structure (SPA) being arranged in a crystal lattice structure;
the first absorbent planar structure (SPA) being N-doped and being produced epitaxially on a substrate (Sub), and the composition of the materials used to produce the at least one layer (Cmm, C1, C2) of the first absorbent planar structure (SPA) being chosen such that:
the first absorbent planar structure (SPA) has an effective valence band (BVeff) formed by a plurality of energy levels (Evhh, Evlh); each energy level (Evhh, Evlh) being occupied by one of:
a first type of positive charge carrier, called heavy holes (hh), having a first effective mass (mhh);
or a second type of positive charge carrier, called light holes (lh), having a second effective mass (mlh) strictly less than the first effective mass (mhh);
the maximum energy level of the effective valence band (BVeff) being occupied by light holes (lh) along the axis (Δ) of the pixel;
the crystal lattice structure of said layer does not exhibit any dislocations resulting from mechanical relaxation of said lattices;
the effective mass of the positive charge carriers along the axis of the pixel (Δ) being less than half the effective mass of the positive charge carriers in directions defining a plane orthogonal to the axis of the pixel (Δ).