Originally, ceramics were used in the electrical field as insulators, often in adverse environments. Think of the extremely large insulation assemblies used on power lines, or the more mundane combined insulator/shields on an old fashioned telegraph pole. If you look at an electric fire, there will be ceramic insulators somewhere, and many types have a heater wire wrapped around a piece of ceramic material.
In electronics, the most obvious examples are in monolithic ceramic chip capacitors and in chip resistors and resistor arrays, the topic of our next sections. But you will also find ceramics within high voltage capacitors, and as the internal support for wire wound resistors, especially high power types. These last often also have a ceramic coating, in the form of a high temperature cement.
Specialised ceramics are used in filters, in ferrites (used for inductors and transformers) and as microwave components, such as circulators.
Structurally, you will find ceramics used as heat sinks, on account of their good thermal properties, especially at high voltage. Many components will include ceramic heat sinks as part of their structure – watch out for the warning signs on packages which contain beryllia, as disassembling these can expose you fatally to beryllia dust.
You will also find ceramics in many packaging solutions, both in manufacturing empty packages for further assembly, and as an interconnective substrate. Many small subassemblies are produced on multilayer ceramic equivalents to a printed circuit board.
In fact, ceramics are used in almost as many applications as polymers, and this is an area we will be exploring in the Module Technology Awareness.