Room-temperature operating extended short wavelength infrared photodetector based on interband transition of InAsSb/GaSb quantum well

Abstract

Here in this paper, we report a room-temperature operating infrared photodetector based on the interband transition of an InAsSb/GaSb quantum well. The interband transition energy of 5-nm thick InAs 0.91 Sb 0.09 embedded in the GaSb barrier is calculated to be 0.53 eV (2.35 µm), which makes the absorption range of InAsSb cover an entire range from short-wavelength infrared to long-wavelength infrared spectrum. The fabricated photodetector exhibits a narrow response range from 2.0 µm to 2.3 µm with a peak around 2.1 µm at 300 K. The peak responsivity is 0.4 A/W under −500-mV applied bias voltage, corresponding to a peak quantum efficiency of 23.8% in the case without any anti-reflection coating. At 300 K, the photodetector exhibits a dark current density of 6.05×10 −3 A/cm 2 under −400-mV applied bias voltage and 3.25×10 −5 A/cm 2 under zero, separately. The peak detectivity is 6.91×10 10 cm•Hz 1/2 /W under zero bias voltage at 300 K.

A method to extend wavelength into middle-wavelength infrared based on InAsSb/(Al)GaSb interband transition quantum well infrared photodetector*

“…As reported in Ref. [25], because of the quantum confinement modulation in the InAsSb/GaSb quantum well, the effective band gap was enlarged. The interband transition in the structure is from the valence band (E VB ) to the first excited state (E 1 ) of InAsSb QWs.…”

“…Compared the energy band structures of InAs 0.91 Sb 0.09 (5 nm)/GaSb (50 nm) QW structure in Ref. [25], the structure is of type II, the main transition in this structure is from the E VB of InAsSb to E 1 , then the electron is extracted from the quantum well and a response current is formed, but the energy band structures of IQWIP-A and IQWIP-B are of type III, the transport mechanism is different from that of type II. The transition process of the type-III structure is that the electron leaps from the E VB of InAsSb to E 1 , because E 1 of InAsSb is lower than the valance band of GaSb, then the electron is not extracted from the quantum well but absorbed into the valance band of GaSb barrier and recombines with the hole finally, so no response current is generated.…”

“…[19][20][21][22] Based on those phenomena, researchers have fabricated three infrared interband transition quantum well detectors on different substrates, including GaAs-based InGaAs/GaAs QWs detectors, [23] InPbased InAs/InGaAs/InAlAs QWs detectors, [24] and GaSbbased lattice-matched GaSb/InAsSb QWs detectors. [25] All the detectors have successfully proved the effectiveness of utilizing interband transition of QWs as a new method of detecting IR spectra. The above results demonstrate the possibility to fabricate new type of MWIR interband band transition quantum well infrared photodetectors (IQWIPs) based on InAsSb heterostructures within a p-n junction.…”

Realizing photomultiplication-type organic photodetectors based on C 60 -doped bulk heterojunction structure at low bias

“…In short, for 1.6 wt.% C 60 -doped P3HT:PC 61 BM device C, the high R of 1.21 A•W −1 is ∼5-fold higher than that of photodiode-type OPDs (λ = 500 nm, U = −1 V, R = 0.273 A•W −1 ), [6] the high D * of 4.22 × 10 12 Jones is ∼ 4-fold higher than that of PM-type OPDs under the same bias of −1.0 V (λ = 550 nm, P in = 3.09 µW•cm −2 , D * = 1.23 × 10 12 Jones), [16] which is comparable or even superior to some inorganic photodetectors. [7,11,31] Moreover, under the premise of the same EQE, device C shows a much lower working voltage compared with the PM-type OPDs reported in Ref. [8] (−6 V).…”

Mechanism of free electron concentration saturation phenomenon in Te-GaSb single crystal*

“…[1][2][3][4][5] GaSb has also become an excellent substrate for epitaxial growth of various ternary and quaternary III-V compounds due to their well-matched lattice parameters. [6][7][8][9] Irrespective to crystal growth methods, undoped GaSb is p-type with an intrinsic acceptor defect concentration up to 10 17 cm −3 . [10,11] This high concentration of native defects in GaSb substrates may lead to an enhancement of IR absorption and electrical compensation which has a negative effect on fabricating high performance IR detectors.…”