Plasma Jet Printing of Lead-salt based MWIR Photoconductive Detectors

The proposed project will develop all-printed mid-wavelength infrared (MWIR) detectors using lead salt-based active layer for next-generation compact, inexpensive but sensitive and efficient systems. The plasma jet printing technique proposed here offers unique capabilities to deposit/print semiconductors, conductors and dielectrics on large-area substrates with tailored physical, optical, chemical and morphological characteristics. Detectors in the MWIR regime are ideally suited for infrared spectroscopy for employing in chemical, aerosol and other threat detection. Lack of compact and inexpensive detectors prevents widespread adoption and use in the field. The proposed all-printed MWIR detector is expected to provide a paradigm change. The project will print PbS and PbSe for photosensitive layers on silicon substrates along with printing contact metal layers. The major innovation here is printing these active layers instead of epitaxial growth, along with printing the contact electrodes for all-printed photodetectors that will be compatible with  silicon CMOS processing. The Phase I work plan will involve print process development to print PbS photoconductor with silver electrodes on silicon.  The printed detectors will be extensively characterized to evaluate the quantum efficiency, detectivity, responsivity and all other metrics and benchmarked against commercial PbS detectors.