On the internal photoemission spectrum of PtSi/p-Si infrared detectors

Properties of internal photoemission in a PtSi-Si Schottky type infrared detector have been studied. The Fowler plot of the detector's photoyield is found to be nonlinear for values close to the barrier height of the junction. The extended model that takes all scattering mechanisms into account is shown to provide a successful description for the experimental results. The barrier height extracted by this approach is smaller than what is found by using commonly used Fowler analysis. A strong loss of photoresponse has been observed at around 0.4 eV which is the high-energy side of the 3-5 pm atmospheric window. This loss is found to result from the ice formation on the detector's surface during the cooling process and can be minimized by improving the vacuum condition around the detector. (C) 2002 Elsevier Science B.V. All rights reserved.