Low-threshold-voltage thin-film electroluminescent devices

Okamoto, Kenji; Nasu, Y.; Hamakawa, Yoshihiro

doi:10.1109/t-ed.1981.20415

Cited by 54 publications

(4 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several means may be used to modify the radiative lifetime and emission efficiency of an emitter. These include altering the local environment of the luminescence center by putting it in different hosts, in different sites, by changing the local electric field of the center by putting it in a microcavity, by putting the emitter between two metal plates, and by putting the sample in a medium with a high dielectric constant . Modifying by quantum size confinement is a novel way under much attention.…”

Section: Discussionmentioning

confidence: 99%

Structure, Luminescence, and Dynamics of Eu₂O₃ Nanoparticles in MCM-41

et al. 2002

View full text Add to dashboard Cite

The structure, luminescence spectroscopy, and lifetime decay dynamics of Eu 2 O 3 nanoparticles formed in MCM-41 have been investigated. Both X-ray diffraction and high-resolution transmission electron microscopic observations indicate that Eu 2 O 3 nanoparticles of monoclinic structure are formed inside channels of MCM-41 by heating at 140 °C. However, heat treatment at 600 or 700 °C causes migration of Eu 2 O 3 from the MCM-41 channels, forming nanoparticles of cubic structure outside the MCM-41 channels. After heating to 900 °C, some of the cubic Eu 2 O 3 particles change to monoclinic Eu 2 O 3 , and the MCM-41 structure breaks down and a different or disordered phase is formed. The feature of the hypersensitive 5 D 0 f 7 F 2 emission profile of Eu 3+ is used to follow the structural changes. In the luminescence spectrum of the sample prepared at 140 °C, the emission spectrum is dominated by peaks at 615 and 623 nm, while in the other samples a peak at 612 nm is prevalent. Photoluminescence lifetimes show the existence of short (<1 µs) and long (microsecond to millisecond) components for each sample. The fast decay is attributed to quenching by surface states of the nanoparticles or energy transfer to the MCM-41, while the longer time decays show the effects of concentration quenching. The monoclinic sample prepared at 140 °C shows a higher luminescence intensity than the cubic samples or the bulk powder. These observations indicate that MCM-41 as a template can be used for making and stabilizing monoclinic rare earth oxides, which normally are stable only at high temperatures and high pressures. More importantly, the nanophase Eu 2 O 3 /MCM-41 composite materials formed at low temperatures might represent a new type of efficient luminescence material with fast response, with potential applications in lighting and displays.

show abstract

Section: Discussionmentioning

confidence: 99%

Structure, Luminescence, and Dynamics of Eu₂O₃ Nanoparticles in MCM-41

et al. 2002

View full text Add to dashboard Cite

show abstract

“…A great number of electronic applications based on these materials have been proposed. Thin films of ferroelectric oxides are very promising materials for a wide range of applications such as high-value capacitors [1], infrared sensors [2][3][4][5][6], ultrasonic sensors [7], non-volatile ferroelectric memories with low switching voltage [8][9][10] and various electro-optical devices [11,12].…”

Section: Introductionmentioning

confidence: 99%

Structure and Characterization of Sputtered Thin Films Based on Lead Titanate.

et al. 1991

View full text Add to dashboard Cite

Pure and doped lead-titanate (PT) and lead-zirconate-titanate (PZT) thin films have been deposited on platinum-coated silicon by rf-magnetron sputtering from pressed powder targets. The films have been deposited without substrate heating. The amorphous films were then annealed in an oxygen flow. The structure of the films is tetragonal or rhombohedral depending on composition. The electrical resistivity, dielectric permittivity, ferroelectric hysteresis and pyroelectric coefficient are reported.

show abstract

“…BaTiO 3 , PbTiO 3 , and SrTiO 3 thin films have all been successfully utilized as insulating layers in ACTFEL devices. 8,9) Bismuth titanate oxide (Bi 4 Ti 3 O 12 ) is a ferroelectric material, and its properties are on a par with those of barium titanate oxides. The authors have observed good optical transmittance and a strong adhesion of sputtered Bi 4 Ti 3 O 12 films on indium tin oxide (ITO)/glass substrates.…”

Section: Introductionmentioning

confidence: 99%

Improved Optical Transmittance and Crystal Characteristics of ZnS:TbOF Thin Film on Bi₄Ti₃O₁₂/Indium Tin Oxide/Glass Substrate by Using a SiO₂ Buffer Layer

Chia¹,

Yokoyama

Yang

et al. 2006

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

Bi4Ti3O12 thin films are deposited on indium tin oxide (ITO)/glass substrates using RF magnetron sputtering technology and are annealed at 675 °C in a rapid thermal annealing furnace in an oxygen atmosphere. The resulting films have high optical transmittances and good crystalline characteristics. ZnS:TbOF films are then deposited on the Bi4Ti3O12 films, causing the originally highly transparent specimens to blacken and to resemble a glass surface coated with carbon powder. The optical transmittance of the specimen is less than 15% under the visible wavelength range, and neither a crystalline phase nor a distinct ZnS grain structure is evident in X-ray diffractometer (XRD) and scanning electronic microscope (SEM). Secondary ion mass spectrometer (SIMS) analysis reveals the occurrence of interdiffusion between the ZnS and Bi4Ti3O12 layers. This suggests that one or more unknown chemical reactions take place among the elements Bi, S, and O at the interface during the deposition of ZnS:TbOF film on a Bi4Ti3O12/ITO/glass substrate. These reactions cause the visible transmittance of the specimens to deteriorate dramatically. To prevent interdiffusion, a silicon dioxide (SiO2) buffer layer 100 nm thick was grown on the Bi4Ti3O12/ITO/glass substrate using plasma-enhanced chemical vapor deposition (PECVD), then the ZnS:TbOF film was grown on the SiO2 buffer layer. The transmittance of the resulting specimen is enhanced approximately 8-fold in the visible region. XRD patterns reveal the ZnS(111)-oriented phase is dominant. Furthermore, dense, crack-free ZnS:TbOF grains are observed by SEM. The results imply that the SiO2 buffer layer sandwiched between the ZnS:TbOF and Bi4Ti3O2 layers effectively separates the two layers. Therefore, interdiffusion and chemical reactions are prevented at the interface of the two layers, and the crystalline characteristics of the ZnS:TbOF layer and the optical transmittance of the specimen are improved as a result. Finally, the dielectric constant of the stacked structure is lower than that of the single layer structure without SiO2, but the dielectric breakdown strength is enhanced.

show abstract

Low-threshold-voltage thin-film electroluminescent devices

Cited by 54 publications

References 12 publications

Structure, Luminescence, and Dynamics of Eu₂O₃ Nanoparticles in MCM-41

Structure, Luminescence, and Dynamics of Eu₂O₃ Nanoparticles in MCM-41

Structure and Characterization of Sputtered Thin Films Based on Lead Titanate.

Improved Optical Transmittance and Crystal Characteristics of ZnS:TbOF Thin Film on Bi₄Ti₃O₁₂/Indium Tin Oxide/Glass Substrate by Using a SiO₂ Buffer Layer

Contact Info

Product

Resources

About

Low-threshold-voltage thin-film electroluminescent devices

Cited by 54 publications

References 12 publications

Structure, Luminescence, and Dynamics of Eu2O3 Nanoparticles in MCM-41

Structure, Luminescence, and Dynamics of Eu2O3 Nanoparticles in MCM-41

Structure and Characterization of Sputtered Thin Films Based on Lead Titanate.

Improved Optical Transmittance and Crystal Characteristics of ZnS:TbOF Thin Film on Bi4Ti3O12/Indium Tin Oxide/Glass Substrate by Using a SiO2 Buffer Layer

Contact Info

Product

Resources

About

Structure, Luminescence, and Dynamics of Eu₂O₃ Nanoparticles in MCM-41

Structure, Luminescence, and Dynamics of Eu₂O₃ Nanoparticles in MCM-41

Improved Optical Transmittance and Crystal Characteristics of ZnS:TbOF Thin Film on Bi₄Ti₃O₁₂/Indium Tin Oxide/Glass Substrate by Using a SiO₂ Buffer Layer