In this paper, i reviewed the processing steps of LTCC (Low-Temperature Co-Fired Ceramics), and the fabricating of embedded channels, especially the modified lamination process, the use of sacrificial volume material (SVM) and the modified co-firing process needed to fabricate deformation-free structures.
The pressure characteristic of the gases generated during the thermal decomposition of starch was determined. The results of this experiment shows, that there are two pressure peaks during this phase, and that the temperature, where these pressure peaks occurred, depends on the heating profile.
The maximum pressure which the substrate can tolerate was determined, the substrate consisted 6 layers of Dupont 951 LTCC and it contained a closed, embedded channel with the following parameters: 45mm*1mm*0.5mm. The computed maximum pressure was 64 191 Pa.
I examined the effects of different channel widths and lengths. Different channels were co-fired with different profile. There were channels with same length but different width and with same volume but different length the results indicate that the channel lengths are the most important factor, because at 10 C/min the shortest channel was intact but all others were destroyed. With 8 C/min co-firing profile only the longest channel was split and with 6 C/min all channels were intact.
From these results I created a modified firing profile, which has two regions where its heating rate was slowed down, these two regions are the pressure peaks from the first experiment.