Material advancements, alternative terminations, and improved processing technologies have led to the development of even smaller, ultraminiature capacitors

By
Daniel West, Field Application
Engineer, AVX

To
date, the evolution of electronic components such as capacitors, resistors,
diodes, and RF filters has trended toward continued miniaturization and, where
possible, added functionality. Material
advancements, alternative terminations, and improved processing technologies
have led to the development of even smaller, ultraminiature capacitors.
Ultraminiature multilayer ceramic capacitors (MLCCs), for example, were
achieved through material advancements including smaller particle size, thinner
dielectrics, and alternative termination technologies.

Capacitor size reductions can also be achieved by increasing
the functionality of a same-sized capacitor with fewer capabilities. Physical
miniaturization can pose significant component design challenges, and pushing
the limits of electronic component functionality can be even more difficult.

Improvements
across multiple scientific fields have contributed to these designs, but the
most notable progress includes purer ceramic, tantalum, and thin-film materials
and improved processes, such as closed-loop manufacturing (CLM). The improved ability to remove impurities from raw
materials and process them using CLM techniques plays a key role in component
capabilities, reliability, and electrical and thermal stability.

These
shifts have enabled extremely accurate computer-aided design (CAD) models,
which can be translated into marketable, real-world parts. Inventive
combinations of other techniques, including packaging designs, fine copper
terminations, and photolithography have further expanded components for
miniature circuit designs.

Key
drivers

OEMs and their electronics designers are
looking for miniaturized parts to optimize circuit and system performance,
satisfy physical design requirements, and improve product aesthetics. Smaller
parts also typically operate at higher speeds with lower parasitics, making
them more compatible with integrated circuit (IC) advancements.

Miniaturized capacitor use has evolved from
very specialized applications to more mainstream markets. Some highlights
include:

  • Defense:
    The Torpedo Data Computer (TDC) was one of the first electromechanical analog
    computers small enough to fit within a submarine and was used during WWII (1939–1945)
    to automatically track targets.

This
chart depicts decreasing parasitic inductance (ESL) by case size and packaging
type.

 

 

  • Aerospace:
    Launch costs of roughly $10,000 per pound, extreme operating conditions, and
    the potential risk to human lives required capacitors to deliver improved
    functionality and utmost reliability in the most size- and weight-efficient
    packages possible.

 

AVX SRC9000 TBM Series tantalum caps

AVX
developed and supplied the 630
space-level, SRC9000 TBM Series ultra-low-ESR,
multi-anode tantalum capacitors
that are responsible for powering Curiosity’s ChemCam laser module.

  • Consumer: Commercial
    versions of advanced defense, space-grade, and other high-reliability
    capacitors shrank living-room radios down to portable boomboxes and then
    cassettes, CDs, and MP3 players; turned vacuum-tube televisions into flat screens;
    and rotary phones into wireless, mobile, and now smartphones, which contain about
    1,000 MLCCs in slim and lightweight form factors with high functionality.

In this slideshow, EBN looks at the ongoing
development of miniaturized capacitors and the technology behind them. Click on
the image below
to read the rest
.

 

slide 4