Investigation On The Preparation And Properties Of CeO₂ Thin Film Electroluminescence Devices Based On Silicon

With the development of information technology,the more rapid and accurate information transmission is required.Conventional silicon-based integrated circuits are facing many challenges and the research has reached a bottleneck.Metal interconnection is encountering challenges of the speed limitations of electronics and large heat dissipation,for instance.In order to solve these problems,silicon-based optoelectronic integration is recognized as a promising candidate for multifunctional applications.Silicon-based light-emitting devices have attracted great attention for several past years.Rare earth ions doped devices offer potential applications in silicon based optoelectronic integration.Therefore,Cerium dioxide?CeO₂?is chosen to be the materials for Silicon-based light-emitting devices,owing to the cubic fluorite structure,excellent chemical stability,high dielectric constant?-26?and so on.In this paper,CeO₂ and Ce₂Si₂O₇ devices were prepared,and the kinds of rare earth ions(Er³⁺+,Eu³⁺,Sm³⁺,Yb³⁺,Tb³⁺? Nd³⁺)were doped in these devices,respectively.The emissions in the range of visible to near-infrared were obtained and the properties of the devices were studied.Firstly,CeO₂ films light-emitting devices were deposited on Si wafers by electron-RF magnetron sputtering technique.White electroluminescence belonging to CeO₂ defects were obtained.The emissions centered at 450 nm,550 nm and 650 nm.The electrical properties were investigated with the crystallinity of films.Then,the Eu³⁺ ions were doped in the CeO₂ device.By increasing the conductivity and oxygen vacancy content of film,the Eu³⁺ ions improved the luminescent properties of the device.Secondly,CeO₂:Er³⁺,CeO₂:Eu³⁺,CeO₂:Sm³⁺ and CeO₂:Yb³⁺ films light-emitting devices were prepared.The characteristic photoluminescence and electroluminescence of Er³⁺,Eu³⁺,Sm³⁺ and Yb³⁺ ions were obtained from these devices,respectively.The luminescent mechanisms were discussed and the electrical properties were investigated with the ions doping concentration.Then,Uhe Zn²⁺ ions were doped in CeG₂:Er³⁺ device and the Tb₂O₃ layers were added to CeO₂:Eu³⁺ and CeO₂:Sm³⁺.By increasing the conductivity of the devices,the voltage were decreased and the electroluminescence intensities were increased.Thirdly,CeO₂ films were annealed in reducing atmosphere and the Ce₂Si₂O₇ films were formed with CeO₂ and SiOx.The photoluminescence and electroluminescence centered at 400 nm was obtained from the devices,which was attributed to the 5d?4f transition of the Ce³⁺ The electrical properties were investigated with the crystallinity of films.Finally,Ce₂Si₂O₇:Tb³⁺,Ce₂Si₂O₇:Yb³⁺ and Ce2Si207:Nd³⁺ films light-emitting devices were prepared.The characteristic photoluminescence and electroluminescence of Tb³⁺,Yb³⁺ and Nd³⁺ ions were obtained from these devices,respectively.The luminescent mechanisms were discussed and the electrical properties were investigated with the ions doping concentration.The intense green emissions were obtained from Ce₂Si₂O₇:Tb³⁺film devices,which were attributed to the 5D4?7FJ?J=6,5,4,3?transitions of the Tb³⁺and the Tb³⁺ was excited by the energy transfer from Ce³⁺.