Quantum Dot Infrared Photodetector Patents 2026
Quantum Dot Infrared Photodetector Patents 2026
QDIPs span epitaxial III-V self-assembled arrays and colloidal quantum dot solution-processed devices. CQD-on-CMOS monolithic integration is the fastest-growing vector in this dataset, with filings from 1999 through 2025.
Two Paradigms Converging in Infrared Detection
Quantum dot infrared photodetectors encompass two structurally distinct paradigms. Epitaxial self-assembled QDIPs use III-V semiconductor quantum dots—predominantly InAs dots in GaAs or AlGaAs matrices grown via molecular beam epitaxy—to exploit intersubband transitions enabling normal-incidence detection across MWIR (3–5 µm) and LWIR (8–12 µm) bands, a capability denied to competing QWIPs by quantum selection rules.
The colloidal quantum dot (CQD) paradigm uses chemically synthesized nanocrystals—principally PbS, PbSe, HgTe, HgSe, and emerging III-V materials—solution-deposited onto substrates including silicon read-out integrated circuits. Size-tunable bandgaps enable spectral coverage from NIR (~0.9 µm) through SWIR (1–2.5 µm) to MWIR and LWIR (3–15 µm), with intraband absorption in heavily doped CQDs extending coverage to 5–9 µm without mercury-based materials.
The foundational QDIP patent was filed by the National Research Council of Canada in 1999, establishing the core self-assembled concept using InAs quantum dots for intersubband photodetection. The 2013–2019 period featured enhancement architecture innovation, including the University of Massachusetts plasmonic QDIP FPA family and Sharp Corporation’s voltage-tunable dual-band quantum dot-quantum well hybrid detectors filed across US and EP jurisdictions.
The 2020–2025 period in this dataset signals a decisive pivot toward CQD integration with silicon electronics. Semiconductor Components Industries filed stacked CQD SWIR imager architectures in 2024–2025, Apple filed a quantum film display-integrated sensor in 2023, and the University of Milano-Bicocca filed a novel LWIR CQD nanostructure device in 2025. In retrieved records, the University of Massachusetts holds the most concentrated single-technology patent family with 6 active US grants.
Technology Cluster Distribution and Filing Trends
Patent records in this dataset cluster into four primary technology approaches, with colloidal QD solution-processed devices representing the fastest-growing filing segment since 2018. Filing activity spans from the foundational 1999 National Research Council of Canada patent through to active 2025 filings.
Patent Records by Technology Cluster in This Dataset
Colloidal QD solution-processed photodetectors represent the largest and most recently active cluster in this dataset, followed by epitaxial III-V barrier-engineered QDIPs and surface plasmon enhancement architectures.
↗ Click bars to exploreQDIP Patent Filing Activity by Period in This Dataset
Filing activity in this dataset accelerated sharply in the 2018–2025 period, reflecting the pivot toward CQD-on-CMOS integration and consumer electronics applications, compared to earlier periods dominated by epitaxial III-V architectures.
↗ Click bars to exploreQDIP Applications Across Defense, Consumer, Industrial, and Environmental Domains
QDIP technology addresses infrared sensing needs across four distinct deployment contexts, from multi-color focal plane arrays for defense thermal imaging to room-temperature CQD arrays for industrial thermography and consumer biometric sensing. Each domain draws on distinct wavelength ranges and device architectures documented in this dataset.
Defense & Night Vision FPAs
The earliest QDIP FPA patent, filed by Koch and assigned to Gula Consulting LLC (2005, US/WO), describes multi-color QDIP arrays hybridized to CMOS readout circuits for surveillance and night vision. Applied NanoFemto Technologies LLC (2014, US) demonstrated a 640×512 pixel QDIP FPA for defense-relevant thermal imaging at elevated operating temperatures, targeting high-operating-temperature (HOT) MWIR/LWIR sensing.
Focal Plane ArraysEnvironmental Gas Sensing LWIR
Mitsubishi Heavy Industries, Ltd. (2018, EP) designed QDIP structures with Bragg-reflection elements and quantum dot transitions spanning 4–4.5 µm to include the 4.257 µm CO₂ absorption line for environmental monitoring. National University Corporation Nagoya University (2013, US) contributed related infrared detector architectures targeting gas detection. The LWIR range (4–15 µm) overlaps with methane and other trace gas absorption bands.
Gas DetectionConsumer Electronics & AR/VR
Apple Inc. (2023, US) filed a quantum film photodetector embedded under a consumer display panel to detect reflected IR for proximity or face-detection sensing. Quantum Advanced Solutions Ltd (2024, WO/GB) filed a QD eye-tracking system using PbS/HgTe QDs achieving ≥40% external quantum efficiency at 940 nm and ≥10% EQE at 1100–2500 nm for AR/VR headsets. These filings mark a decisive entry of QD IR detectors into mass-market consumer devices.
Consumer BiometricsIndustrial Thermography & Medical
A 2019 literature study demonstrated a 320×256 pixel HgCdTe CQD array operating at room temperature on a commercial silicon ROIC, directly targeting industrial inspection and medical thermal imaging cost barriers. The University of Milano-Bicocca (2025, WO) filed a nanostructured LWIR device targeting uncooled detection at 8–15 µm for medical and industrial thermography. These developments address the high operating temperature challenge identified in 2021 and 2023 HOT literature as the central obstacle for the field.
Thermal ImagingKey Patent Assignees in QDIP Technology — Dataset Snapshot
In this dataset, the University of Massachusetts holds the most concentrated single-technology patent family with 6 active US grants on plasmonic QDIP FPA enhancement (2014–2020). Fujitsu Limited accounts for 4 US patents (2007–2013) in retrieved records, focused on III-V QDIP dark current suppression. Innovation is fragmented across university technology transfer offices and corporate R&D divisions, with no single entity controlling the full stack from CQD synthesis to integrated imaging module in this dataset.
Top Assignees by Filing Count — QDIP Dataset Snapshot (Retrieved Records)
↗ Click bars to exploreUniversity of Massachusetts
The University of Massachusetts holds 6 active US patent grants (2014–2020) in this dataset, the most concentrated single-technology patent family in the retrieved records. All patents cover backside-configured surface plasmonic grating structures integrated with InAs QDIP focal plane arrays to enhance photocurrent via surface plasmon resonance local field amplification. The family includes patents granted in 2017, 2018, 2019, and 2020, with at least one divisional application confirming active prosecution.
United StatesFujitsu Limited
Fujitsu Limited filed 4 US patents (2007–2013) in this dataset covering III-V compound semiconductor QDIP architectures for dark current suppression. Key innovations include AlAs barrier layers covering InAs quantum dots (2010, US) and first/second barrier layer configurations flanking the quantum dot layer with band gaps larger than the intermediate layer (2013, US). Fujitsu primarily prosecuted US and EP patents rather than filing exclusively in Japan, indicating international IP protection strategy for this technology period.
Japan — US jurisdictionFive Vectors Shaping QDIP Innovation Through 2025
Based on the most recent filings (2023–2025) in this dataset, five technology vectors define where the QDIP field is heading: CQD-on-CMOS monolithic integration, consumer biometric and AR/VR sensing, LWIR room-temperature nanostructured detection, optical communications integration, and meta-lens photonic concentration.
CQD-on-CMOS Monolithic Integration
Semiconductor Components Industries, LLC (2025, US; 2024, WO) filed stacked CQD SWIR imager architectures placing CQD photodetector arrays directly above standard CMOS substrates with intermetal dielectric redistribution layer interconnects. This architecture eliminates the flip-chip hybridization bottleneck that constrained earlier FPA cost and yield, representing the highest-velocity development vector in this dataset. Toppan Inc.’s parallel CQD sensor family (2018–2025) also targets CMOS-compatible manufacturing using spherical PbS, PbSe, and CdHgTe quantum dots.
LWIR Room-Temperature Nanostructured Detectors
The University of Milano-Bicocca (2025, WO) filed a nanostructured LWIR device targeting uncooled detection at 8–15 µm for medical and industrial thermography, directly addressing the high operating temperature (HOT) challenge. Literature from 2021 and 2023 identifies HOT design as the central obstacle for the field. A separate 2019 study demonstrated a 320×256 pixel HgCdTe CQD FPA on a commercial silicon ROIC operating at room temperature, with productization readiness projected within the 2025–2027 timeframe based on current filing trajectories.
Epitaxial III-V QDIP vs. Colloidal QD Photodetector: Key Dimensions
Click any row to explore further.
| Dimension | Epitaxial III-V QDIP | Colloidal QD (CQD) Photodetector |
|---|---|---|
| Primary Materials | InAs quantum dots in GaAs or AlGaAs matrix | PbS, PbSe, HgTe, HgSe, In(As,P) nanocrystals |
| Growth Method | Molecular beam epitaxy (MBE), Stranski-Krastanov strain-driven | Chemical synthesis; spin-coating, drop-casting, or ink-jet deposition |
| Spectral Coverage | MWIR (3–5 µm) and LWIR (8–12 µm) via intersubband transitions | NIR (~0.9 µm) through SWIR (1–2.5 µm) to MWIR/LWIR (3–15 µm) |
| Normal-Incidence Detection | Yes — enabled by 3D quantum confinement (advantage over QWIPs) | Yes — inherent to colloidal nanocrystal absorption |
| CMOS Compatibility | Requires flip-chip hybridization to silicon ROIC | Direct deposition on silicon ROIC; back-end-of-line compatible (<400°C budget) |
| Key IP Example | Fujitsu Limited AlAs barrier QDIP (2010, US); University of Massachusetts plasmonic FPA (2014–2020, US) | University of Chicago HgSe intraband MWIR (2016, US); Semiconductor Components Industries CQD SWIR (2025, US) |
| Fabrication Cost | High — MBE growth, wafer-scale epitaxy, flip-chip bonding | Lower potential — solution processing, wafer-scale spin-coating on silicon |
| Operating Temperature | Below HgCdTe benchmarks per 2009 and 2021 literature; HOT designs closing gap | Room-temperature operation demonstrated (320×256 px HgCdTe CQD FPA, 2019) |
Frequently Asked Questions: Quantum Dot Infrared Photodetectors
QDIPs exploit intersubband or intraband transitions within three-dimensional quantum-confined energy levels, enabling normal-incidence photodetection across MWIR and LWIR bands. QWIPs are denied this capability by quantum selection rules, which restrict them from detecting normally incident light without grating couplers.
Colloidal QD photodetectors can cover spectral ranges from near-IR (~0.9 µm) through SWIR (1–2.5 µm) to MWIR and LWIR (3–15 µm) within a single materials platform. Intraband absorption in heavily doped CQDs—such as HgSe demonstrated by the University of Chicago (2016, US)—extends coverage to 5–9 µm without the need for mercury-based compounds.
The University of Massachusetts holds 6 active US patent grants (2014–2020) in this dataset, all covering backside-configured surface plasmonic grating structures integrated with InAs QDIP focal plane arrays. This is identified as the most concentrated single-technology patent family in the retrieved records.
CQD-on-CMOS integration, as filed by Semiconductor Components Industries, LLC (2025, US; 2024, WO), places CQD photodetector arrays directly above standard CMOS substrates with intermetal dielectric redistribution layer interconnects. This eliminates the flip-chip hybridization bottleneck that constrained earlier focal plane array cost and yield, and is identified as the highest-velocity development vector in this dataset.
A 2019 literature study demonstrated a 320×256 pixel HgCdTe CQD focal plane array operating at room temperature on a commercial silicon ROIC. High-operating-temperature MWIR/LWIR QDIPs remain below HgCdTe performance benchmarks per the 2009 and 2021 literature but are closing the gap, with productization readiness projected within the 2025–2027 timeframe based on current filing trajectories.
The US is dominant, representing approximately 60% of patent records in this dataset, reflecting activity from US universities, defense-linked firms such as Applied NanoFemto Technologies, and consumer electronics companies including Apple and Semiconductor Components Industries. EP filings come from Mitsubishi Heavy Industries, Toppan Inc., and University of Milano-Bicocca. Japanese corporate assignees (Fujitsu, Sharp, Toppan) primarily prosecute US and EP patents. CN, WO, IN, and ZA jurisdictions also appear in the dataset.
Data and insights on this page are based on a limited patent and literature dataset and are for reference only. Figures may not represent the complete technology landscape.