Type-II superlattice detectors for high-performance SWaP detectors and HOT HD applications at IRnova

Delmas, M.; Ivanov, Ruslan; Ramos, David; Žurauskaitė, L.; Evans, Dean; Rihtnesberg, David; Bendrot, Linnea; Smuk, Sergiy; Smuk, Anton; Becanovic, Smilja; Almqvist, Susanne; Tinghag, Pia; Fattala, Saad; Costard, E.; Höglund, Linda

doi:10.1117/12.2663854

Cited by 3 publications

(1 citation statement)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While these configurations aim to minimize surface leakage currents and maximize the fill factor by not exposing the mesa sidewalls with an interpixel trench, not fully delineating the pixel penalizes the MTF values mainly due to high electrical crosstalk [6], [12], [13]. However, state-of-the-art MWIR T2SL detectors implement a fully delineated geometry with appropriate passivation of the mesa sidewalls to suppress surface leakage currents [14], [15]. In addition, thanks to this geometry, optical concentration in the pixel has been observed as the pixel pitch reduces, thus mitigating the fill factor loss due to the trench etching and increasing the signal-to-noise ratio in smaller pixel size [7], [16], [17].…”

mentioning

confidence: 99%

Simulation and Characterization of the Modulation Transfer Function in Fully Delineated Type-II Superlattices Infrared Detectors

Ramos,

Delmas,

Ivanov

et al. 2024

IEEE Trans. Electron Devices

View full text Add to dashboard Cite

The modulation transfer function (MTF) in fully delineated 15 µm pitch type-II superlattice (T2SL) midwave infrared (IR) detectors is studied theoretically and experimentally. Theoretically, a 2-D model to simulate the spot scan (SS) profile is presented and used to compute the MTF as a function of the wavelength and the array geometry (pitch size, trench width). The dependence of the detector trench on the MTF is also evaluated experimentally by the edge spread function (ESF) method according to the ISO12233 standard. The experimental results show an excellent agreement with the theoretical model, reporting an MTF of 0.61 and 0.60 at the Nyquist frequency for 1 and 2 µm trench, respectively. With the simulation model, the effect of the increased optical crosstalk for smaller pixel pitch is discussed as a function of the trench width (0.5, 1, and 2 µm) and incidence angle up to ±30 • . Simulation results show MTF values at the Nyquist frequency between 0.61-0.62, 0.58-0.60, and 0.55-0.57 with an average degradation of 1%, 2%, and 7% at an angle of ±30 • compared to normal incidence for the 10, 7.5, and 5 µm pitch, respectively.

show abstract

mentioning

confidence: 99%

Simulation and Characterization of the Modulation Transfer Function in Fully Delineated Type-II Superlattices Infrared Detectors

Ramos,

Delmas,

Ivanov

et al. 2024

IEEE Trans. Electron Devices

View full text Add to dashboard Cite

show abstract

Optical concentration in fully delineated mid-wave infrared T2SL detectors arrays

Ramos,

Delmas,

Höglund

et al. 2023

Applied Physics Letters

View full text Add to dashboard Cite

The dependence of quantum efficiency (QE) on fill factor and pixel pitch is studied theoretically and experimentally in fully delineated type-II superlattice (T2SL) detectors. Theoretically, a 2-dimensional simulation model is used to compute the absorption in the array geometry, which shows an insensitivity of the optical response to the fill factor. This is a result of the photodiode array (PDA) geometry concentrating the light in the pixel area. QE measurements on PDAs with varying pixel pitch (from 225 to 10 μm) and fill factors (from 98% to 64%) confirm this independence of the QE on the fill factor and results in a 50% increase in the photocurrent density in 10 μm pitch PDAs compared to 225 μm pitch PDAs. Furthermore, measurements of the dark current density vs pixel size revealed an absence of surface leakage in these PDAs, which, combined with the increased photocurrent density results in an improved signal-to-noise ratio when reducing the pitch in these T2SL detectors. Finally, this result resolves the QE-modulation transfer function trade-off, as the electrical isolation of the pixel is carried out without impacting the QE of the array.

show abstract

Type-II superlattice HD detectors at IRnova for eSWIR and MWIR applications

Höglund,

Delmas,

Ivanov

et al. 2024

Infrared Technology and Applications L

View full text Add to dashboard Cite

In this paper, the first extended SWIR (eSWIR, 1-2.5 µm) focal plane array (FPA) results, based on IRnova's 2.5 µm cutoff T2SL design are presented. High sensitivity is demonstrated with a signal to noise ratio (SNR) of 215 @ 50% well fill and a dynamic range of 1750 for a full well size of 118 ke-of the CTIA ROIC. Good uniformity across the detectors is evidenced by narrow SNR histograms, uniform response maps and low signal non-uniformity (~1 %). This work is part of the development route towards large footprint (2048 × 512 pixels, 15 µm pitch) HD space prototype eSWIR FPAs, currently performed within the EU-project STEP (Silicon and T2SL EuroPean collaboration for a non-dependent supply chain for large eSWIR FPAs). In addition, a first preview of the HD FPA performance enabled by IRnova's midwave infrared (MWIR) T2SL small pitch technology is presented, showing an NETD of 32 mK at 120 K with F/3, 60 Hz and 10 ms integration time.

show abstract

Type-II superlattice detectors for high-performance SWaP detectors and HOT HD applications at IRnova

Cited by 3 publications

References 5 publications

Simulation and Characterization of the Modulation Transfer Function in Fully Delineated Type-II Superlattices Infrared Detectors

Simulation and Characterization of the Modulation Transfer Function in Fully Delineated Type-II Superlattices Infrared Detectors

Optical concentration in fully delineated mid-wave infrared T2SL detectors arrays

Type-II superlattice HD detectors at IRnova for eSWIR and MWIR applications

Contact Info

Product

Resources

About