Europium doped yttrium oxide (Eu:Y2O3) phosphor thin films were grown using a pulsed laser deposition (PLD) technique at varying growth conditions. The structural characterization carried out on a series of Eu:Y2O3 films grown on (100) silicon at substrate temperatures in the range of 250–600 °C and oxygen pressure in the range of 10−5 Torr to 200 mTorr indicated that films were preferentially (111) oriented. Measurements of photoluminescence and cathodoluminescence properties of laser deposited Eu:Y2O3 thin films and powder used for laser target showed that the best in situ grown films were ∼10%–22% as bright as Eu:Y2O3 powder. A postdeposition annealing treatment of Eu:Y2O3 films led to further improvements in their brightness (up to ∼70% with respect to Eu:Y2O3 powder), with cluster sizes of <400 nm.

Recent advances in the phosphors used for field emission displays (FEDs) are discussed. After reviewing the range of voltages and phosphors being used in first generation devices, the improved properties of future generation phosphors are reviewed. Specifically, next generation displays will require better low voltage efficiencies, chromaticity, saturation behavior, and maintenance. Possible routes to achieve these improvements are discussed. The improved understanding of the role of charging and surface recombination effects on cathodoluminescent intensity and efficiency is reviewed. An improved understanding of electron beam-stimulated surface chemical reaction effects on the degradation of phosphor is presented. It is concluded that recent research efforts have created a new level of understanding of FED phosphors, and this should lead to the necessary improvements in properties.

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Using a combination of infrared absorption and small-angle x-ray scattering on hydrogenated amorphous silicon alloy films and efficiency measurements of solar cells with intrinsic layers prepared under nominally identical conditions to those for the deposition of the films, we observe a correlation between microstructure in the films and solar cell performance. With increasing microvoid density, both the initial and light-degraded performance of solar cells are found to deteriorate.

Degradation of ZnS and Y2O2S cathodoluminescent (CL) phosphors has been studied at 1–4 keV using Auger electron spectroscopy simultaneous with CL. The data are consistent with an electron stimulated surface chemical reaction (ESSCR) which led to destruction of ZnS and formation of a surface nonluminescent ZnO layer as well as injection of oxygen point defects into the near-surface region. In the case of Y2O2S:Eu, the electron beam stimulated removal of S and formation of Y2O3:Eu in the presence of 1×10−6 Torr of oxygen. A model is presented which predicts that degradation by the ESSCR should increase with pressure in the vacuum, depend exponentially on electron dose, increase as the primary beam energy was reduced below 4 keV, and depend upon the type of gas present in the vacuum. These trends were demonstrated from the experimental data.