The Effect of Forming Gas Annealing on Pt/(Ba,Sr)TiO3/Pt Thin Film Capacitors for Future Dram Applications: Electrical Properties and Degradation Mechanisms

AbstractWe have used electrical characterization and secondary ion mass spectroscopy (SIMS) to investigate the influence of hydrogen or deuterium (H/D) on the degradation of the electrical properties of Pt/Ba0.7Sr0.3TiO3/Pt thin film capacitors after forming gas exposure. Deuterium SIMS depth profiling shows that high deuterium concentrations can be incorporated into Pt/BSTO/Pt capacitors after forming gas annealing. The increase in H/D concentration in the film is accompanied by an increase in the leakage and dielectric relaxation current density. Voltage offsets in the capacitance-applied voltage (C-VA) characteristics after forming gas exposure at lower temperatures (20 °C) and a suppression in the capacitance density near zero applied D.C. bias after forming gas exposure at higher temperatures, suggests that one effect of forming gas exposure to Pt/BSTO/Pt thin film capacitors is to introduce positive space charge into the BSTO film. Using an equivalent model for a ferroelectric thin film capacitor, which incorporates lower permittivity interfacial layers and a nonlinear electric field-electric displacement relationship for the film interior, the effects of a uniform distribution of positive space charge on the theoretical C-VA and current density applied voltage (J-VA) characteristics are investigated. It is shown the model can account for many of the observed changes that occur in the experimental C-VA and J-VA characteristics after forming gas exposure.

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Direct observation of traps responsible for positive space charge in alternating-current thin-film electroluminescent devices

Applied Physics Letters ◽

10.1063/1.123462 ◽

1999 ◽

Vol 74 (8) ◽

pp. 1120-1122 ◽

Cited By ~ 4

Author(s):

Alex N. Krasnov

Keyword(s):

Thin Film ◽

Space Charge ◽

Direct Observation ◽

Alternating Current ◽

Electroluminescent Devices ◽

Positive Space Charge ◽

Positive Space

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A contribution to the theory of impulse corona and the long spark

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1964.0128 ◽

1964 ◽

Vol 280 (1380) ◽

pp. 23-36 ◽

Cited By ~ 20

Keyword(s):

Space Charge ◽

Electron Impact ◽

Applied Voltage ◽

Reasonable Agreement ◽

Impact Ionization ◽

Approximate Theory ◽

Positive Space Charge ◽

Negative Impulse ◽

Photo Ionization ◽

Positive Space

An approximate theory of the propagation of positive impulse corona is presented based on a model in which electrons are produced by photo-ionization and are multiplied by electron impact ionization in the strong fields near the tip of the corona filament. The filament extends by attracting electrons into itself, leaving behind a positive space charge. Formulae are derived which enable speeds of propagation, electron densities and filament radii to be predicted as a function of applied voltage in terms of fundamental atomic crosssections, some of which are not accurately known. The theory was compared with the results of one particular experiment and reasonable agreement was obtained. The extension to negative impulse corona and subsequent stages of the breakdown process is briefly discussed.

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The structure of the impulse corona in a rod/plane gap I. The positive corona

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1970.0026 ◽

1970 ◽

Vol 315 (1520) ◽

pp. 1-25 ◽

Cited By ~ 34

Keyword(s):

Spatial Distribution ◽

Electric Field ◽

Space Charge ◽

Negative Ions ◽

Corona Discharges ◽

Theoretical Derivation ◽

Plane Electrode ◽

Positive Space Charge ◽

Positive Ion ◽

Positive Space

The dissipation of space charge following the growth of impulse corona discharges in positive rod/earthed plane gaps has been measured with an electrostatic fluxmeter. A method is described to determine the spatial distribution and magnitude of the space charge together with the associated electric field. Initial positive ion densities of up to 100 μC m -3 have been found. The total positive space charge deposited in a 40 cm gap at 160 kV is 500 nC. Electrons emitted from the plane electrode as a result of corona channels crossing the gap are shown to be trapped in the discharge space as negative ions. The recovery of the gap over several seconds is largely due to ionic drift to the electrodes. A theoretical derivation of the rate of deionization agrees with observed values.

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Continuous Positive Space Charge in Silicone Rubber Insulation

2018 IEEE 2nd International Conference on Dielectrics (ICD) ◽

10.1109/icd.2018.8514729 ◽

2018 ◽

Author(s):

Weiwang Wang ◽

Shengtao Li ◽

Dongri Xie ◽

Yasuhiro Tanaka

Keyword(s):

Space Charge ◽

Silicone Rubber ◽

Positive Space Charge ◽

Positive Space

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Thermally Stimulated Currents in the Range of Unity Gain Factor

Zeitschrift für Naturforschung A ◽

10.1515/zna-1971-0507 ◽

1971 ◽

Vol 26 (5) ◽

pp. 819-823

Author(s):

J. A. Bragagnolo ◽

G. Dussel ◽

K. W. Böer ◽

G. A. Dussel

Keyword(s):

Space Charge ◽

Space Charge Region ◽

Thermal Quenching ◽

Gain Factor ◽

Thermally Stimulated Current ◽

Thermally Stimulated Currents ◽

Positive Space Charge ◽

Unity Gain ◽

Positive Space

Abstract Thermally stimulated current-curves in CdS platelets with slit electrodes change their character when the photoelectric gain-factor increases above one. Here the photocurrent remains essentially frozen-in up to temperatures at which marked thermal quenching sets in. A positive space charge region is assumed to be responsible for the frozen-in photocurrent. A reliable TSC-analysis of the trap distribution can be conducted only for gain factors considerably below one.

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