Threshold voltage instability and polyimide charging effects of LTPS TFTs for flexible displays

AbstractIn this paper, we investigate the Vth shift of p-type LTPS TFTs fabricated on a polyimide (PI) and glass substrate considering charging phenomena. The Vth of the LTPS TFTs with a PI substrate positively shift after a bias temperature stress test. However, the Vth with a glass substrate rarely changed even with increasing stress. Such a positive Vth shift results from the negative charging of fluorine stemmed from the PI under the gate bias. In fact, the C–V characterization on the metal–insulator-metal capacitor reveals that charging at the SiO2/PI interface depends on the applied gate bias and the PI material, which agrees well with the TCAD simulation and SIMS analyses. As a result, the charging at the SiO2/PI interface contributes to the Vth shift of the LTPS TFTs leading to image sticking.

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Effects of polyimide curing on image sticking behaviors of flexible displays

Scientific Reports ◽

10.1038/s41598-021-01364-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hyojung Kim ◽

Jongwoo Park ◽

Sora Bak ◽

Jungmin Park ◽

Changwoo Byun ◽

...

Keyword(s):

Coefficient Of Thermal Expansion ◽

Curing Temperature ◽

Indium Gallium Zinc Oxide ◽

Threshold Voltage Shift ◽

Flexible Displays ◽

Metal Insulator Metal ◽

Display Technology ◽

Bias Temperature Stress ◽

Materials Used ◽

Charging Effect

AbstractFlexible displays on a polyimide (PI) substrate are widely regarded as a promising next-generation display technology due to their versatility in various applications. Among other bendable materials used as display panel substrates, PI is especially suitable for flexible displays for its high glass transition temperature and low coefficient of thermal expansion. PI cured under various temperatures (260 °C, 360 °C, and 460 °C) was implemented in metal–insulator–metal (MIM) capacitors, amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFT), and actual display panels to analyze device stability and panel product characteristics. Through electrical analysis of the MIM capacitor, it was confirmed that the charging effect in the PI substrates intensified as the PI curing temperature increased. The threshold voltage shift (ΔVth) of the samples was found to increase with rising curing temperature under negative bias temperature stress (NBTS) due to the charging effect. Our analyses also show that increasing ΔVth exacerbates the image sticking phenomenon observed in display panels. These findings ultimately present a direct correlation between the curing temperature of polyimide substrates and the panel image sticking phenomenon, which could provide an insight into the improvement of future PI-substrate-based displays.

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Modeling, Fabrication, and Electrical Testing of Metal-Insulator-Metal Diode

10.21236/ada553952 ◽

2011 ◽

Cited By ~ 4

Author(s):

Terrance O'Regan ◽

Matthew Chin ◽

Cheng Tan ◽

Anthony Birdwell

Keyword(s):

Metal Insulator ◽

Metal Insulator Metal

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Reentrant Metal-Insulator-Metal Transition in (DMe-DCNQI)2Cu System - Competition between Spin and Free Electron Degrees of Freedom-

Current Inorganic Chemistry ◽

10.2174/1877944104666140825202424 ◽

2014 ◽

Vol 4 (2) ◽

pp. 110-121 ◽

Cited By ~ 2

Author(s):

Yutaka Nishio ◽

Naoya Tajima ◽

Koji Kajita

Keyword(s):

Free Electron ◽

Degrees Of Freedom ◽

Metal Insulator ◽

Insulator Metal Transition ◽

Metal Insulator Metal

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Structural Integrity of Three-dimensional Metal-insulator-metal (3-D MIM) Capacitor Embedded in Fully-filled Cu Through-silicon Via (TSV)

IEEE Transactions on Components Packaging and Manufacturing Technology ◽

10.1109/tcpmt.2021.3067322 ◽

2021 ◽

pp. 1-1

Author(s):

Ye Lin ◽

Hong Yu Li ◽

Chuan Seng Tan

Keyword(s):

Structural Integrity ◽

Three Dimensional ◽

Metal Insulator ◽

Through Silicon Via ◽

Metal Insulator Metal

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Hyperspectral Molecular Orientation Mapping in Metamaterials

Applied Sciences ◽

10.3390/app11041544 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1544

Author(s):

Meguya Ryu ◽

Yoshiaki Nishijima ◽

Shinya Morimoto ◽

Naoki To ◽

Tomoki Hashizume ◽

...

Keyword(s):

Molecular Orientation ◽

Field Enhancement ◽

Chemical Mapping ◽

Metal Insulator ◽

Orientation Mapping ◽

Metal Insulator Metal ◽

Finger Printing ◽

Thermal Emitter ◽

Ir Bands ◽

Sub Wavelength

The four polarisation method is adopted for measurement of molecular orientation in dielectric nanolayers of metal-insulator-metal (MIM) metamaterials composed of gold nanodisks on polyimide and gold films. Hyperspectral mapping at the chemical finger printing spectral range of 4–20 μμm was carried out for MIM patterns of 1–2.5 μμm period (sub-wavelength). Overlay images taken at 0,π4,π2,3π4 orientation angles and subsequent baseline compensation are shown to be critically important for the interpretation of chemical mapping results and reduction of spurious artefacts. Light field enhancement in the 60-nm-thick polyimide (I in MIM) was responsible for strong absorption at the characteristic polyimide bands. Strong absorbance A at narrow IR bands can be used as a thermal emitter (emittance E=1−R), where R is the reflectance and A=1−R−T, where for optically thick samples the transmittance is T=0.

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Nonstoichiometric Nanolayered Ni/NiO/Al2O3/CrAu Metal–Insulator–Metal Infrared Rectenna

ACS Applied Nano Materials ◽

10.1021/acsanm.0c03012 ◽

2021 ◽

Vol 4 (3) ◽

pp. 2470-2475 ◽

Cited By ~ 1

Author(s):

Ayendra Weerakkody ◽

Amina Belkadi ◽

Garret Moddel

Keyword(s):

Metal Insulator ◽

Metal Insulator Metal

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Design of a Liquid-Crystal-Tunable Terahertz Demultiplexer Based on a Metal-Insulator-Metal Waveguide

Applied Sciences ◽

10.3390/app9040644 ◽

2019 ◽

Vol 9 (4) ◽

pp. 644

Author(s):

Xue-Shi Li ◽

Naixing Feng ◽

Yuan-Mei Xu ◽

Liang-Lun Cheng ◽

Qing Liu

Keyword(s):

Liquid Crystal ◽

Electric Field ◽

Metal Insulator ◽

Resonance Modes ◽

External Bias ◽

Bias Electric Field ◽

Metal Waveguide ◽

Metal Insulator Metal ◽

Fabry Perot ◽

Mim Waveguide

A tunable demultiplexer with three output channels infiltrated by liquid crystal (LC) is presented, which is based on a metal-insulator-metal (MIM) waveguide. The operating frequencies of the three output channels can be tuned simultaneously at will by changing the external bias electric field applied to the LC. By analyzing the Fabry-Pérot (FP) resonance modes of the finite-length MIM waveguide both theoretically and numerically, the locations of the three channels are delicately determined to achieve the best demultiplexing effects. Terahertz (THz) signals input from the main channel can be demultiplexed by channels 1, 2 and 3 at 0.7135 THz, 1.068 THz and 1.429 THz, respectively. By applying an external electric field to alter the tilt angle of the infiltrating LC material, the operating frequencies of channels 1, 2 and 3 can be relatively shifted up to 12.3%, 9.6% and 9.7%, respectively. The designed demultiplexer can not only provide a flexible means to demultiplex signals but also tune operating bands of output channels at the same time.

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