Date of Award
Master of Science in Electrical Engineering (MSEE)
A study of thermally generated conductivity and photoconductivity in thin layers of silver sulfide is presented.
Silver layers were vacuum deposited on sapphire substrates and transformed into silver sulfide in a sulfur atmosphere at 120° C. The dark current of single element sensors was investigated as a function of temperature and photocurrent was measured as a function of photon flux and wavelength . The samples were photosensitive to radiation in the spectral range 0.7 μm to 1 .8 μm. A maximum photoresponse occurred at a wavelength of 0.8 μm. The photocurrent in general increased with decreasing temperature. The absorption edge for Ag2s at 90 K was found to be at 1.2 μm making the calculated energy gap 1.0 eV. From dark current measurements, recombination centers were found at 0.66 eV below the conduction band.
Vidicon type targets made from silver sulfide layers were also investigated and showed an image fade-out effect with a time constant in the order of seconds. Target resolution was found to exceed 10 1p/mm and the targets responded to incident photon flux levels of 30 μW/cm2.
Aceto, Paul Joseph, "Infrared Photoconductivity in Thin Silver Sulfide Films" (1976). Open Access Master's Theses. Paper 817.