STTR PHASE I: Metalorganic Chemical Vapor Deposition Growth on Plasic for Low-Voltage Electroluminescent Displays

*9632164弗农该项目第一阶段将在塑料基板上开发薄膜电致发光显示器。用金属有机化学气相沉积(MOCVD)法在高温Kapton衬底上生长了以锌为基质的没食子酸锌(ZnGa204)荧光粉。离子注入将引入发光中心，并在不损害衬底的情况下对荧光粉进行脉冲激光退火。第一阶段将展示MOCVD可以在与Kapton兼容的温度下沉积氧化物荧光粉，Kapton是一种可使用到~450℃的塑料。由于Kapton和其他聚酰亚胺材料在光学上不透明，因此将开发具有顶部(非衬底)侧发光的结构。在离子注入发光中心的过程中，衬底温度将通过水冷却来控制。通过脉冲紫外光(UV)激光对掺杂剂进行活化和晶体增强，以免降解塑料衬底。佛罗里达大学将使用准分子激光开发适当的紫外线退火法。玻璃衬底将作为实验对照包括在内。SPIRE将通过X射线衍射和电子显微镜比较在塑料和玻璃衬底上MOCVD生长的ZnGa204薄膜的质量，并将对退火态的ZnGa2O4薄膜进行光致发光和阴极发光测试。然后，佛罗里达大学将在玻璃和塑料衬底上制造和测试电致发光设备。第二阶段将包括优化荧光粉生长、发光中心注入和塑料衬底上的激光退火法。发展低温MOCVD高介电常数陶瓷薄膜，以实现更低的工作电压和更高的发光效率。SPIRE的MOCVD氧化物反应器用于沉积荧光粉和高介电体材料，Spire还将尝试通过在同一反应器中快速沉积多层介质-磷光体-介质堆叠来提高电致发光效率和降低制造成本。这项研究将能够在塑料基板上制造平板EL显示器，用于坚固、明亮、轻便的手持信息终端，为苛刻环境中的人员提供更好的图形通信。***

*** 9632164 Vernon This Phase I STTR project will develop thin film electroluminescent displays on plastic substrates. The zinc gallate (ZnGa204) phosphor host will be grown by metalorganic chemical vapor deposition (MOCVD) at ~425 C on a high-temperature Kapton substrate. Luminescent centers will be introduced by ion implantation, and a pulsedlaser anneal of the phosphor without damaging the substrate. Phase I will demonstrate that oxide phosphors can be deposited by MOCVD at temperatures compatible with Kapton, a plastic usable up to ~450 C. Because Kapton, and other polyimide materials, are not optically clear, structures having light emission from the top (nonsubstrate) side will be developed. Substrate temperature will be controlled by water cooling during ion implantation of luminescence centers. Dopant activation and crystal enhancement will be by pulsed ultraviolet (UV) laser annealing, so as not to degrade the plastic substrate. Development of the proper UV anneal, using an excimer laser, will be conducted at the University of Florida. Glass substrates will be included as experimental controls. Spire will compare the quality of MOCVD-grown ZnGa204 films on plastic and glass substrates by x-ray diffraction and electron microscopy, and photoluminescence and cathodoluminescence tests will be performed on annealed ZnGa2O4 films. The University of Florida will then fabricate and test electroluminescent devices on both glass and plastic substrates. Phase II will include optimization of phosphor growth, luminescence-center implantation, and laser annealing on plastic substrates. Low-temperature MOCVD of high-dielectric ceramic films will be developed to achieve lower voltage operation and higher luminescent efficiency. Spire's MOCVD oxide reactor is set up to deposit phosphor as well as high-dielectric materials, and Spire will also attempt to improve electroluminescent efficiency and lower fabrication costs by rapid deposition of multilayer dielectric-phosphor-dielectric stacks in the same reactor. This research will result in the capability to fabricate flat-panel EL displays on plastic substrates for rugged, bright, lightweight, handheld information terminals to provide better graphical communication to personnel in demanding environments. ***