Low temperature co-fired ceramic

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Low temperature co-fired ceramic (LTCC) is a well-established process that has been in use for many years in the microelectronics packaging industry. It is similar to the thick film hybrid process employed for multilayer ceramic capacitors and chip inductors. LTCC technology is especially used for wireless and high-frequency applications. In RF and wireless applications, LTCC technology is also used to make multilayer hybrid integrated circuits, which can include resistors, inductors, capacitors, and active components in the same package. LTCC hybrids have a smaller initial ("non recurring") cost as compared with ICs, making them an attractive alternative for small scale integration devices.

This technology presents advantages compared to other technologies: the ceramic could be fired below 900°C due to a special composition of the material. This permits the co-firing with high conductive materials (silver, copper and gold). LTCC also permit the ability to embed passive elements, such as resistors, capacitors and inductors into the ceramic package; hence the size of the components decreases.

[edit] Printed resistances

The LTCC ceramics are suitable for printing on resistances. With a screen printing method a conductive paste is printed onto the LTCC surface, from which resistances needed in the circuit are generated. These resistances deviate from their desired value (±25%) and are therefore too small to be printed. With Laser trimming one can achieve these resistances with different cut forms to the exact resistance value (±1%) desired. With this procedure, no resistors must be placed on the bare board, thereby allowing a further miniaturization of the printed circuit boards.