Investigation of traps in strained‐well InGaAs/GaAsSb quantum well photodiodes

Abstract

InP-based strained-well InGaAs/GaAsSb quantum well photodiodes with non-zero net strain can be used to extend detection wavelengths well into the mid-infrared region. However, excess dark current due to defects in the structure can be a performance limiting factor in photodiodes of this type. In this reported work, both low-frequency noise spectroscopy and deep level transient spectroscopy were used to investigate traps in prototypical strained-well photodiode heterostructures. Two distinct traps were identified and their electrical and physical properties and distributions have been evaluated.

Elimination of interlayer Schottky barrier in borophene/C4N4 vdW heterojunctions via Li-ion adsorption for tunneling photodiodes

“…3a, to investigate the effect of vertical stacking and Li-ion adsorption on the interfacial separation of hole-electron pairs of bilayer structures. The electron density difference (Dr) is defined as follows: 51,52 DrðyÞ¼ ð r adsorbateþsubstrate ðx;y;zÞdxdzÀ ð r adsorbate ðx;y;zÞdxdzÀ ð r substrate ðx;y;zÞdxdz , N substrate ; (4) in which r adsorbate+substrate (x,y,z), r adsorbate (x,y,z), and r substrate (x,y,z) denote the electron densities of the adsorption system, the isolated adsorbate and substrate at the (x, y, z) point, respectively, and N substrate is the number of atoms in the substrate. All the adsorption systems are electrically neutral, as no external electric field is applied vertically.…”

“…Semiconductor-based photodiodes, as a photoelectric sensing component to convert optical signals into photocurrent, has been widely studied and applied in many areas, such as image sensing, environmental monitoring, surveillance and spectroscopy. [1][2][3][4] Schottky barrier photodiodes are considered superior to p-i-n photodiodes, metal-semiconductor-metal photodiodes, and so on, in terms of their low power consumption, large current, and ultrahigh response speed. [5][6][7][8] Recently, van der Waals (vdW) heterostructures, which are formed by stacking different two-dimensional (2D) semiconductors vertically through vdW forces, have attracted the interest of a growing number of researchers.…”

Defect Characterization of InAs/InGaAs Quantum Dot p-i-n Photodetector Grown on GaAs-on-V-Grooved-Si Substrate

“…In order to make the Lorentzian component more visible from the spectrum, eq (1) is multiplied by f, which is expressed as： In order to probe the physically meaningful trap parameters such as energy and cross section from the measured spectra, the noise spectra at different temperatures and applied bias were measured. By fitting the measured noise spectra with eq (2), the lifetime τi under different temperatures can be extracted [20][21] . From an Arrhenius plot of ln(τT 2 ) versus 1000/T, the energy level of the trap states can be extracted from the slope, and the capture cross section can be found from the intercept 22 .…”

Deep levels analysis in wavelength extended InGaAsBi photodetector

“…The G-R noise arising from deep levels appeared as Lorentzian peaks superimposed on the noise spectra. The detail of LFN measurement can refer to the reference [30][31][32][33].…”

“…The G-R noise arising from deep levels appeared as Lorentzian peaks superimposed on the noise spectra. The detail of LFN measurement can refer to the reference[30][31][32][33].The current noise spectral density is mathematically expressed as[33]: and B are the amplitudes of the G-R and 1/f process, τ i is the time constant of the G-R center, C is the white noise related constant. By plotting the f*S I versus f, the Lorentzian peaks would be more visible, and the time constant τ i under different temperatures can be extracted by Lorentzian fitting.…”