Advanced electrical and stability characterization of untrimmed and variously trimmed thick-film and LTCC resistors

As-fired thick-film resistors have the resistance tolerance within ±20% and this tolerance is increased for smaller components. Therefore the novel trimming methods are necessary for microresistors, especially when they are embedded in LTCC substrate. This paper compares electrical (normalized temperature dependence of resistance, low frequency noise) and stability properties (relative resistance drift, changes of current noise index) of untrimmed, voltage pulse trimmed and laser trimmed unglazed thick-film resistors after step-increased long-term thermal ageing at 162 C, 207 C and 253 C. Moreover the effect of long term exposure (1000 h, 125 C) and thermal shocks (1000 shocks between 55 C and 125 C) is analysed for untrimmed and voltage pulse trimmed buried LTCC resistors. 2004 Elsevier Ltd. All rights reserved.