Although both substrates share many of the same processing steps, the LTCC-M technology has advantages.
The new LTCC-M technology serves as a solution for these high performance circuits and systems.
TABLE I SUBSTRATE PROPERTY COMPARISON Lamina Ceramics LTCC-M Material Property ** Kovar Range of part up to 16 x 16 dimensions (inches) Buried passives yes Buried resistor [+ or -]10 tolerance (%) High K tape yes Ferrite tape yes Hermetic cavities yes x-y shrinkage (%) ~[+ or -]0.
LTCC-M substrates and their integrated components have been subjected to long-term accelerated aging tests such as temperature-humidity-bias storage (at 85 [degrees] C, 85 percent relative humidity, 50 V bias across capacitors) and thermal shock (-55 [degrees] to +125 [degrees] C) without any degradation in their electrical or mechanical properties.
A design kit for the simulation and layout of multilayer LTCC-M substrates containing embedded lumped passive components, surface transmission lines and embedded transmission lines has been developed to make this technology more accessible.
TABLE I LTCC-M MATERIAL PROPERTIES Firing temperature ([degrees] C) 875 to 925 Dielectric constant at 10 kHz (25 [degrees] C) 5.
The model uses components with physical attributes such as width and length, and then all relevant dimensions are calculated based on design rules specific to LTCC-M.
Figure 5 shows an example of the validation of the LTCC-M capacitor circuit model using E M simulation.
Other LTCC-M processing techniques to further increase these Q values are being developed.
Figure 8 shows the look of a schematic entry window containing LTCC-M components.
The LTCC-M technology has been transferred to a merchant supplier, Dielectric Laboratories Inc.
Applications of LTCC-M technology range from single-cavity packages for semiconductor die to complex modules with buried passive components.