X7R Dielectrics for High Energy Density Capacitors
Abstract
This paper summarizes the results of a project dedicated towards the development of dielectrics for high energy density discharge capacitors. The primary goal was to produce capacitors with the following specifications: 1) the capacitors must fit within a space which is 1 x 1 x 0.020″; 2) have at least 0.10 μF over a temperature range -55 ~ 125 °C, at 1000 V; 3) are able to withstand voltage surges to 2000 V without failure; and 4) fast charge/discharge cycle (200 ms to 1000 V, then hold at the voltage for 2 min and discharge through a 150 mΩ resistor with a peak current 2000 A in 200 ns). Key factors to this project were the magnitude of the dielectric constant (K) at high field levels, and the breakdown strength (BDS). Studies on a commercially available X7R composition yielded a dielectric with a K = 920, and an average BDS = 250 kV/cm. Processing studies showed the dielectric could be lapped down to a thickness of 4 mils. Thermal annealing was necessary to retain the mechanical and electrical integrity. These boundary conditions forced the development of a multilayer capacitor instead of the originally conceived single layer capacitor.
Recommended Citation
W. Huebner et al., "X7R Dielectrics for High Energy Density Capacitors," Journal of the Korean Physical Society, vol. 32, no. 4 SUPPL., pp. S1793 - S1797, Korean Physical Society, Jan 1998.
Department(s)
Materials Science and Engineering
International Standard Serial Number (ISSN)
0374-4884
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 1998 Korean Physical Society, All rights reserved.
Publication Date
01 Jan 1998