Next-Generation Infrared Sensors: Innovations in Semiconductor Materials and Applications

Innovative Semiconductor Materials for Infrared Sensors © ryanking999-chronicles - stock.adobe.com

Infrared (IR) sensor technology has made remarkable strides, evolving through three generations of development. A recent study, conducted by Nikolaos Argirusis, Achilleas Achilleos, Niyaz Alizadeh, Christos Argirusis, and Georgia Sourkouni from institutions including MAT4NRG GmbH (Germany), KU Leuven (Belgium), and the National Technical University of Athens (Greece), provides a comprehensive review of the field. Published in Sensors, the research highlights the role of emerging materials in enhancing IR sensors' performance and broadening applications (1).

The Expanding Role of IR Sensors

IR sensors, which detect radiation beyond the visible spectrum, play a crucial role in various applications, including thermal imaging, security, medical diagnostics, environmental monitoring, and space exploration (1,2). The study notes that IR radiation is categorized into short-wave (SWIR, 1–3 µm), mid-wave (MWIR, 3–5 µm), long-wave (LWIR, 8–12 µm), and very long-wave (VLWIR, >12 µm) bands. Each band serves distinct purposes, with MWIR and LWIR particularly significant in thermal imaging and surveillance technologies (1).

Traditional IR detection relies on semiconductor materials such as mercury-cadmium-telluride (MCT), indium antimonide (InSb), and quantum well infrared photodetectors (QWIPs). However, the study emphasizes that advancements in nanotechnology and quantum materials are now reshaping the field, enabling higher performance and new functionalities (1,2).

Emerging Materials Transforming IR Sensing

The study highlights the critical role of new and novel semiconductor materials in the future of IR detection. These include (1):

• Quantum dot infrared photodetectors (QDIPs): Quantum dots (QDs) exhibit unique electronic properties that can improve IR sensor sensitivity, reduce dark current, and enable multicolor detection.
• Graphene and two-dimensional materials: With high carrier mobility and tunable electronic properties, graphene and transition metal dichalcogenides (TMDs) show promise for high-performance IR detection with lower cooling requirements.
• Colloidal quantum dots (CQDs) and Type-II Superlattices: These materials enhance infrared absorption and enable operation at higher temperatures compared to traditional bulk semiconductors.

Despite these advancements, the study acknowledges challenges, such as the low quantum efficiency of QDIPs and fabrication difficulties in large-area graphene-based detectors. Nevertheless, ongoing research into material uniformity and nanofabrication techniques is expected to overcome these hurdles.

Advances in Sensor Architecture and Functionality

The research categorizes IR sensors into photon detectors and thermal detectors based on their detection principles. Photon detectors, such as photoconductive and photovoltaic sensors, generate an electrical response upon photon interaction with charge carriers. Thermal detectors, including pyroelectric and thermoelectric sensors, detect changes in material properties induced by IR radiation absorption (1,2).

Additionally, the study explores active and passive IR sensors. Active IR sensors emit and detect infrared light, making them valuable for proximity sensing in robotics and security applications. Passive IR (PIR) sensors, commonly used in motion detection, rely solely on the infrared radiation emitted by objects (1).

Future Prospects: AI and Bio-Inspired Sensor Systems

The study outlines a vision for the future of IR sensors, where advanced electronics and artificial intelligence (AI) will play an integral role in sensor functionality. AI-driven adaptive sensor systems could enhance real-time image processing, improve signal interpretation, and enable bio-inspired solutions, such as multi-spectral detection in a single pixel (1).

Furthermore, researchers anticipate significant strides in miniaturization and cost reduction, making high-performance IR detection more accessible for consumer electronics, medical diagnostics, and environmental monitoring. Innovations in multi-spectral and hyperspectral imaging are also expected to enhance applications in agriculture, food safety, and climate science (1).

Infrared sensor technology is undergoing a transformative shift, driven by breakthroughs in quantum materials, nanotechnology, and AI integration. While challenges remain in material optimization and large-scale fabrication, the future of IR detection promises enhanced sensitivity, lower costs, and expanded applications. As the field continues to evolve, IR sensors will play an increasingly critical role in technological advancements across industries (1,2).

References

(1) Argirusis, N.; Achilleos, A.; Alizadeh, N.; Argirusis, C.; Sourkouni, G. IR Sensors, Related Materials, and Applications. Sensors 2025, 25 (3), 673. DOI: 10.3390/s25030673

(2) Yu, X.; Ji, Y.; Shen, X.; Le, X. Progress in Advanced Infrared Optoelectronic Sensors. Nanomaterials 2024, 14 (10), 845. DOI: 10.3390/nano14100845