HgTe Nanocrystal Inks for Extended Short‐Wave Infrared Detection. Issue 15 (20th May 2019)

• Record Type: Journal Article
• Authors: Martinez, Bertille; Ramade, Julien; Livache, Clément; Goubet, Nicolas; Chu, Audrey; Gréboval, Charlie; Qu, Junling; Watkins, William L.; Becerra, Loïc; Dandeu, Erwan; Fave, Jean Louis; Méthivier, Christophe; Lacaze, Emmanuelle; Lhuillier, Emmanuel
• Is Part Of: Advanced optical materials. Volume 7:Issue 15(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-05-20
• Subjects: focal plane array -- HgTe -- nanocrystals -- photodiodes -- short‐wave infrared; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.201900348
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: Short‐wave infrared (IR) detection is currently driven by InGaAs technology which has limited the perspective of cost effectiveness and consequently slows the development of IR sensors. Since organic electronics are ineffective in this wavelength range, an alternative to conductive polymers is the use of colloidal quantum dots (CQDs) which exhibit strongly tunable IR absorption. In this paper, the extended short‐wave IR (2.5 µm cut‐off) is focused on to expand the capabilities of InGaAs, while using HgTe nanocrystals as the active material. Previous devices based on this material suffer from a low responsivity due to weak absorption (few percents). The integration of HgTe nanocrystals is presented in ink form to build thick (up to 600 nm), strongly absorbing nanoparticle films. This ink is integrated into a diode, allowing one to boost the responsivity by two orders of magnitude and the detectivity by one order of magnitude compared to previous HgTe devices at the same wavelength. Detectivity reaches 3 × 10 9 Jones, while the time response is found to be 370 ns for room temperature and 0 V bias operation. Finally, the material is integrated into a focal plane array which is used to determine laser beam profile. Abstract : Ink made from HgTe nanocrystals is used to fabricate a strongly absorbing film in the extended short‐wave infrared. This material is then integrated into a photodiode and a focal plane array.