Polymer infrared photo-detector with high sensitivity up to 1100 nm

En Chen Chen, Shin Rong Tseng, Yu Chiang Chao, Hsin Fei Meng*, Chih Feng Wang, Wen Chang Chen, Chian Shu Hsu, Sheng Fu Horng

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    19 Citations (Scopus)


    We reported a low band-gap conjugated polymer, poly[2,3-bis(4-(2- ethylhexyloxy)phenyl)-5,7-di(thiophen-2-yl)thieno[3,4-b]pyrazine] (PDTTP), was studied for the near infrared (NIR) photo-detector application. PDTTP shows intense absorption in NIR wavelength (to 1000 nm) and the estimated optical and electrochemical band-gaps of PDTTP are quite small around 1.15 eV and 1.08 eV, respectively. The low band-gap and the extended long wavelength absorption originates from the introduction of alternating TP units when its parent polythieno[3,4-b]pyrazine shows excellent narrow band-gap properties. Therefore, the relatively low band-gap and intense absorption in long wavelength of PDTTP make itself a promising candidate for near-infrared photo-detector. The hole mobility of the PDTTP measured from the bottom contact field effect transistor is around 1.40 × 10-3 cm2/V s with a on/off ratio of 2100. The photo-detector based on bulk hetero-junction PDTTP and (6,6)-phenyl-C61-butyric acid methyl ester blend (PCBM) has the incident photon-to-electron conversion efficiency 28.9% at 1000 nm (-5 V) and 6.2% at 1100 nm (-5 V). This photo-detector can be operated at a high-speed of 1 MHz. The experimental result suggests the potential applications of low band-gap conjugated polymers on near-infrared photo-detectors.

    Original languageEnglish
    Pages (from-to)1618-1622
    Number of pages5
    JournalSynthetic Metals
    Issue number15-16
    Publication statusPublished - 2011 Aug 1


    • Low band-gap
    • Near infrared
    • Photo-detector
    • Polymer

    ASJC Scopus subject areas

    • Electronic, Optical and Magnetic Materials
    • Condensed Matter Physics
    • Mechanics of Materials
    • Mechanical Engineering
    • Metals and Alloys
    • Materials Chemistry


    Dive into the research topics of 'Polymer infrared photo-detector with high sensitivity up to 1100 nm'. Together they form a unique fingerprint.

    Cite this