DC and AC electrical properties and long-term stability of LTCC resistors

Interesting problems occur due to mutual dependencies between various DC and AC electrical properties as well as with correlation between electrical characteristics and long-term stability of electronic components. This paper presents wide and systematic investigations of electrical and stability properties of buried and surface low temperature co-fired ceramics (LTCC) resistors. Various resistors were made from commercially available 100 kΩ/sq. resistive ink on/in three different LTCC tapes from various manufacturers. The influence of resistor/tape combinations (kind of LTCC green tape, resistor position) and resistor aspect ratio on sheet resistance, temperature dependence of resistance in a wide temperature range, low frequency noise, voltage nonlinearity, AC impedance spectra and long-term stability of thermally aged resistors were measured, analysed and discussed. Many interesting relations were found. For example, it was proved that LTCC resistors (made from the same resistive ink but in different technological variants) with significant dimensional effects were characterised by larger 1/f noise and larger nonlinearity. However, dimensional effects did not affect AC properties and long term stability of such resistors