Phosphor films

Physical Concepts of High-Field, Thin-Film Electroluminescence Devices

“…LCD), the great drawback that it adds appreciably to the complexity of the LSI circuit "panel + memo- The lifetime which is the most important feature governing marketability has been tested by Sharp for its devices. It is lo4 h [14] or according to more recent statements lo6 h to 50% of initial brightness for non-memory devices.…”

Effect of Mn composition of characterization of Zn1−xMnxS epilayers

“…They are easily transformed into octahedrally coordinated stable ␣ form by heating. [11][12][13] Thin film electroluminescent displays with ZnS:Mn as active layers, presented by Inoguchi and Mito, 14 remain the most commonly used and most efficient devices among all electroluminescence ͑EL͒ displays. [7][8][9] The crystal structure of bulk Zn 1−x Mn x S is a zinc-blende structure in the range of Mn composition x Ͻ 0.1 and a wurtzite structure 0.1Ͻ x Ͻ 0.43.…”

“…6 Theoretical calculations and experimental measurement revealed a lattice constant for ␤-MnS close to that of GaAs. [14][15][16][17] Since the observation of ϳ18% photoluminescent quantum efficiency from Mn-doped ZnS nanocrystal by Bhargava and Gallagher,18 ZnS:Mn semiconductor nanocrystals have been widely recognized as an efficient electroluminescent phosphor. 10 At values of x beyond these ranges, phase segregations occur.…”

Improved electroluminescence of ZnS:Mn thin films by codoping with potassium chloride

“…5 Finally, the stability ͑aging͒ is critical to ACTFEL device manufacturing and product lifetime. 1,2,6 Aging causes the gray level produced by a given voltage on an EL pixel to shift with operating time, resulting in residual ''ghost images.'' Often, ACTFEL devices are operated for a short time at higher frequencies and larger drive voltages to cause short term aging which will stabilize the B -V characteristic.…”

“…The characteristics and causes of aging vary widely depending on the type of ACTFEL device, the driving conditions, and the insulators. [6][7][8] The band shifting associated with the onset of conduction in an ACTFEL device is illustrated in the simplified schematic diagram of Fig. 2.…”