Nanoimaging of Organic Charge Retention Effects: Implications for Nonvolatile Memory, Neuromorphic Computing, and High Dielectric Breakdown Devices

Alkali-free flat panel display glass is produced in large quantity and has excellent electrical insulating properties at high temperature. Aluminum borosilicate glass with alkaline-earth modifier has low sodium content and low dielectric loss (tan δ <0.1 at 250°C), high dielectric breakdown strength (109 V/m) and excellent high temperature stability. In addition, roll-to-roll processing of thin glass sheet has been demonstrated and glass capacitors that are configured in a coil. Excellent high power capability of these glasses was confirmed by analytical, finite element, and finite difference modeling. The modeling work indicates that a combination of hybrid electrode design and effective heat loss at the interface can further extend power capability of glass capacitors. Alkali-free glass is an ideal candidate material for high temperature capacitors.

Download Full-text

Dielectric Breakdown Mechanism of Perovskite-Structured Ceramics

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/cicmt-tp43 ◽

2015 ◽

Vol 2015 (CICMT) ◽

pp. 000116-000120 ◽

Cited By ~ 3

Author(s):

Takuya Hoshina ◽

Mikio Yamazaki ◽

Hiroaki Takeda ◽

Takaaki Tsurumi

Keyword(s):

High Temperature ◽

Room Temperature ◽

Oxygen Vacancies ◽

Dielectric Breakdown ◽

Breakdown Strength ◽

Dielectric Breakdown Strength ◽

Breakdown Mechanism ◽

High Dielectric ◽

Measurement Efficiency ◽

Breakdown Model

We precisely measured the dielectric breakdown strength of SrTiO3, CaTiO3, and CaZrO3 ceramics as a function of temperature, and revealed the dielectric breakdown mechanism of the ceramics. For the dielectric breakdown test, ceramics specimens with a lot of round-bottom holes were prepared. Using the specimens, the breakdown positions were stabilized and a reliability of breakdown strength was improved as well as the measurement efficiency. As a result of the dielectric breakdown tests, it was found that the dielectric breakdown strength decreased with increasing permittivity at room temperature and the permittivity dependence of breakdown strength obeyed Griffith type energy release rate model. At high temperature above 100ºC, the dielectric breakdown mechanism of SrTiO3 and CaTiO3 ceramics was explained by an intrinsic breakdown model. In contrast, an intrinsic dielectric breakdown of CaZrO3 ceramics didn't occur in the measurement temperature range up to 210ºC. To obtain a high dielectric breakdown strength at high temperature, the dielectric permittivity is required to be low to some extent and the defect concentration of oxygen vacancies should be minimized in the perovskite-structured oxide.

Download Full-text

Thermal poling of alkaline earth boroaluminosilicate glasses with intrinsically high dielectric breakdown strength

Journal of Applied Physics ◽

10.1063/1.3703679 ◽

2012 ◽

Vol 111 (8) ◽

pp. 083519 ◽

Cited By ~ 21

Author(s):

Nicholas J. Smith ◽

Michael T. Lanagan ◽

Carlo G. Pantano

Keyword(s):

Alkaline Earth ◽

Dielectric Breakdown ◽

Breakdown Strength ◽

Dielectric Breakdown Strength ◽

Thermal Poling ◽

High Dielectric

Download Full-text

CrFe 2O4 - BiFeO3 Perovskite Multiferroic Nanocomposites – A Review

Material Science Research India ◽

10.13005/msri/110206 ◽

2014 ◽

Vol 11 (2) ◽

pp. 128-145 ◽

Cited By ~ 6

Author(s):

Ratnakar Pandu

Keyword(s):

Nonvolatile Memory ◽

Ferroelectric Properties ◽

Tungsten Bronze ◽

Random Access ◽

Frequency Dispersion ◽

Processing Technique ◽

Conductive Composites ◽

Peak Broadening ◽

High Dielectric ◽

Ferroelectric Hysteresis

Though semiconductor technology has advanced significantly in miniaturization and processor speed the “ideal” nonvolatile memory - memory that retains information even when the power goes is still elusive. There is a large demand for non-volatile memories with the popularity of portable electronic devices like cell phones and note books. Semiconductor memories like SRAMs and DRAMs are available but, such memories are volatile. After the advent of ferroelectricity many materials with crystal structures of Perovskite, pyrochlore and tungsten bronze have been derived and studied for the applications in memory devices. Ferroelectric Random Access Memories (FeRAM) are most promising. They are nonvolatile and have the greater radiation hardness and higher speed. These devices use the switchable spontaneous polarization arising suitable positional bi-stability of constituent ions and store the information in the form of charge. This paper is focused on the synthesis and characterizations of BiFeO3 and xCrFe2O4-(1-x) BiFeO3 nanoceramics which are most promising FeRAM materials. The effect of various-dopant-induced changes in structural, dielectric, ac impedance, ferroelectric hysteresis, mechanism of the dielectric peak broadening and frequency dispersion have been addressed. It also deals with low temperature processing technique of those nanoceramics which has high dielectric and ferroelectric properties. These studies can be further extended to reinforce BiFeO3 and CrFeO4 materials with carbon nanotubes to obtain conductive composites using appropriate techniques.

Download Full-text