Electrical Aging Effect on Breakdown and Charge Trap Characteristics of Polyimide Films with Different Thickness in LN2

Electrical aging in lead zirconate titanate (PbZrxTi1−xO3) thin films has been intensively studied from a macroscopic perspective. However, structural origins and consequences of such degradation are less documented. In this study, we have used synchrotron radiation to evaluate the behavior of ferroelectric domains by X-ray diffraction (XRD). The sample was loaded with an AC triangular bias waveform between ±10 V with a number of cycle varying from one up to 108. At each step of the aging procedure, XRD spectra had been collected in situ during the application of an electric field on a capacitor. The fine analysis of the (200) pseudo-cubic peak structure allows to separate the evolution of the volume of a/c tetragonal and rhombohedral domains along the electrical biasing. Throughout the aging, both intrinsic and extrinsic responses of tetra and rhombohedral domains are altered, the behavior depending on the observed phase. This methodology opens up new perspectives in the comprehension of the aging effect in ferroelectric thin film.

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Influence of photoconductivity on the study of trap levels in polyimide films by photo-stimulated discharge

Modern Physics Letters B ◽

10.1142/s0217984916504108 ◽

2016 ◽

Vol 30 (34) ◽

pp. 1650410 ◽

Cited By ~ 1

Author(s):

Li-Juan He ◽

Xiong Yang ◽

Hui-Qin Niu ◽

Zhen-Hua Yuan ◽

Da-Wei Li ◽

...

Keyword(s):

Charge Transfer ◽

Discharge Current ◽

Charge Transfer Complex ◽

Polyimide Films ◽

Charge Trap ◽

Trap Levels ◽

Trapped Charge

In this paper, the distribution of the charge trap levels in polyimide (PI) films was investigated by using photo-stimulated discharge (PSD) technique, which was to explore the effect of photoconductivity on photo-stimulated discharge current. The PSD spectra show that the photo-stimulated discharge current of the PI films is mainly distributed in the range of 649–320 nm, but there are two significant current peaks when the wavelength is 300 nm and 244 nm, respectively. By studying the reason of generating two current peaks, it is concluded that the two current peaks are not generated by trapped charge de-trapping but generated by photoconductivity of charge-transfer complex in the PI films. According to the research, it is concluded that the trap levels in PI films are mainly distributed in the range of 1.92 eV–3.88 eV.

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The Potential Barrier and Thermal Stability Dependence on PI Thickness of Al/PI/c-Si Schottky Diode

Iraqi Journal of Science ◽

10.24996/ijs.2020.61.12.12 ◽

2020 ◽

pp. 3235-3241

Author(s):

Hussein Kh. Rasheed ◽

Aseel A. Kareem

Keyword(s):

Thermal Stability ◽

Thermal Decomposition ◽

Interfacial Layer ◽

Average Distance ◽

Amic Acid ◽

Complete Conversion ◽

Polyimide Films ◽

Ft Ir ◽

Ir Analysis ◽

Different Thickness

This research investigated the effectiveness of using different thickness values of polyimide (PI) interfacial layer in order to improve electrical and thermal properties of Al/ PI /c-Si capacitor. The PI spectra produced by poly(amic acid) (PAA) were characterized by using FT-IR analysis. After imidization of PAA, some absorption peaks vanished, whereas PI peaks appeared, due to the complete conversion of PAA to PI. The results show that thermal decomposition resistance of polyimide films increases with the increase of polyimide thickness, because of the increase of the imide bond and the decrease of the average distance between amide groups.

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Electron microscopy and diffraction studies of polyimides

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074069 ◽

1983 ◽

Vol 41 ◽

pp. 28-29

Author(s):

O.C. de Hodgins ◽

K. R. Lawless ◽

R. Anderson

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Structural Features ◽

Inert Atmosphere ◽

Polyimide Films ◽

Resolution Electron ◽

The Matrix ◽

High Resolution Electron Microscope ◽

Diffraction Patterns ◽

Polymeric Samples

Commercial polyimide films have shown to be homogeneous on a scale of 5 to 200 nm. The observation of Skybond (SKB) 705 and PI5878 was carried out by using a Philips 400, 120 KeV STEM. The objective was to elucidate the structural features of the polymeric samples. The specimens were spun and cured at stepped temperatures in an inert atmosphere and cooled slowly for eight hours. TEM micrographs showed heterogeneities (or nodular structures) generally on a scale of 100 nm for PI5878 and approximately 40 nm for SKB 705, present in large volume fractions of both specimens. See Figures 1 and 2. It is possible that the nodulus observed may be associated with surface effects and the structure of the polymers be regarded as random amorphous arrays. Diffraction patterns of the matrix and the nodular areas showed different amorphous ring patterns in both materials. The specimens were viewed in both bright and dark fields using a high resolution electron microscope which provided magnifications of 100,000X or more on the photographic plates if desired.

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The Ultrastructure of Monkey Gingival Epithelium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006009x ◽

1967 ◽

Vol 25 ◽

pp. 16-17

Author(s):

C.N. Sun

Keyword(s):

Epithelial Cells ◽

Macaca Nemestrina ◽

Stratum Granulosum ◽

Solution Ph ◽

Gingival Epithelial Cells ◽

Stratum Spinosum ◽

Cell Layers ◽

Gingival Epithelium ◽

The Individual ◽

Different Thickness

The present study demonstrates the ultrastructure of the gingival epithelium of the pig tail monkey (Macaca nemestrina). Specimens were taken from lingual and facial gingival surfaces and fixed in Dalton's chrome osmium solution (pH 7.6) for 1 hr, dehydrated, and then embedded in Epon 812.Tonofibrils are variable in number and structure according to the different region or location of the gingival epithelial cells, the main orientation of which is parallel to the long axis of the cells. The cytoplasm of the basal epithelial cells contains a great number of tonofilaments and numerous mitochondria. The basement membrane is 300 to 400 A thick. In the cells of stratum spinosum, the tonofibrils are densely packed and increased in number (fig. 1 and 3). They seem to take on a somewhat concentric arrangement around the nucleus. The filaments may occur scattered as thin fibrils in the cytoplasm or they may be arranged in bundles of different thickness. The filaments have a diameter about 50 A. In the stratum granulosum, the cells gradually become flatted, the tonofibrils are usually thin, and the individual tonofilaments are clearly distinguishable (fig. 2). The mitochondria and endoplasmic reticulum are seldom seen in these superficial cell layers.

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Aging effect on joint moment generation strategy in successful reactive-recovery from unexpected slips

PsycEXTRA Dataset ◽

10.1037/e577432012-009 ◽

2005 ◽

Author(s):

Jian Liu

Keyword(s):

Aging Effect ◽

Joint Moment

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Study on thermal degradation of high power LEDs during high temperature and electrical aging

Information Science and Management Engineering II (Set) ◽

10.2495/isme20140421 ◽

2014 ◽

Author(s):

Fei Yuan ◽

Kailin Pan ◽

Tao Lu ◽

Xin Wang ◽

Bin Zhou

Keyword(s):

High Temperature ◽

Thermal Degradation ◽

High Power ◽

Electrical Aging

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Non-Visible Defect Analysis of OTP Device

ISTFA 2011: Conference Proceedings from the 37th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2011p0198 ◽

2011 ◽

Author(s):

C.Q. Chen ◽

G.B. Ang ◽

Z.X. Xing ◽

Y.N. Hua ◽

Z.Q. Mo ◽

...

Keyword(s):

Trap Center ◽

Data Retention ◽

Auger Analysis ◽

Cross Sectional ◽

Critical Dimensions ◽

Charge Trap ◽

Root Cause ◽

Transmission Electron ◽

Electrical Analysis ◽

Visible Defect

Abstract Several product lots were found to suffer from data retention failures in OTP (one time program) devices. PFA (physical failure analysis) was performed on these devices, but nothing abnormal was observed. Cross-sectional TEM (transmission electron microscopy) revealed no physical defects or abnormal CDs (critical dimensions). In order to isolate the failed layer or location, electrical analysis was conducted. Several electrical simulation experiments, designed to test the data retention properties of OTP devices, were preformed. Meilke's method [1] was also used to differentiate between mobile ion contamination and charge trap centers. Besides Meilke's method, a new electrical analysis method was used to verify the analysis results. The results of our analysis suggests that SiN charge trap centers are the root cause for the data retention failures, and the ratio of Si/N is the key to charge trap center formation. Auger analysis was used to physically check the Si/N ratio of OTP devices. The results support our hypothesis. Subsequent DOE (Design Of Experiment) experiments also confirm our analysis results. Key Words: OTP, data retention, Non-visible defect, AFP, charge trap center, mobile ion.

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