Miniaturized Embossed Low Resistance Fine Line Coils in LTCC

Embedded ceramic coils stand out because of their excellent dielectric, thermal, and RF properties. However the relatively high sheet resistance (low thickness) of printed thick-film conductors restricts their functionality for applications where current values of several amps are needed. Using embossed structures it is possible to manufacture conductors with increased thickness and low resistance on LTCC tapes. The manufacturing process for wide conductors with high dimensional accuracy was shown in previous publications. In this work fine line embossed structures with line widths and spaces of 50 and 75 μm respectively were realized. The cross section of the embossed channels was about 50 μm. The fine line screen printing, stencil printing, and the photo definable Fodel® processes were used to fill the small structures with thick-film ink. The whole process was used to manufacture several types of low resistance coils in LTCC that can be used for current values up to approximately 3 A. They were realize...