Here is the abstract you requested from the CICMT_2007 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Comparison of High Resolution Patterning Technologiesfor LTCC Microwave Circuits|
|Keywords: LTCC, Microwave, Thin Film|
|Low Temperature Co-fired Ceramics (LTCC) is being widely used for microwave circuits. The BMBF funded R&D-project KERAMIS focuses on larger implementation of functionality in LTCC substrates to allow designs with „standard“ MMICs. Target applications are circuits for multimedia satellite communications. In order to add more functionality in LTCC, current patterning limits of line width and line separation (100 µm) need to be extended. Four different technologies are considered candidates for higher resolution: a) fine line printing technology with special screens, b) photo-imageable pastes, c) etching of thick film conductors (co- and post-fired) and d) thin films on LTCC. For this purpose, a test coupon was designed and manufactured by the consortium members. The artwork contains lines, line transitions, ring resonators (microstrip and stripline), edge-coupled filters, DC blocking structures, and various lines for DC resistance testing. The smallest gap definition is 50µm. Two substrate materials, Du Pont tape 951 and 943, are included in the study. Besides the main frequency band of interest in the project (17-22 GHz), these structures have been characterised up to 50 GHz.Electrical results are correlated to physical measurements of the features (line width, spaces and tolerances). Data are evaluated with respect to performance, manufacturability, and yield. Results show excellent performance for screen printed structures and demonstrated the importance of mask tuning to achieve optimum resolution (under etching etc.). Filter insertion loss at 40 GHz and steepness of skirts were almost independent on the patterning technology.|
|Jens Mueller, Head of Research Group
TU Ilmenau, ZIC MacroNano®
Ilmenau, Thueringen D-98693,