Tolerance-optimized RF structures in LTCC for mm-wave frequencies applications

Abstract

Low-Temperature Co-fired Ceramic (LTCC) is a well-established technology for microwave space products and RF structures and it is a good candidate for these new frequency bands. Embedded passives are available to increase the density of integration even more. At higher frequencies, structures become smaller and more prone to process tolerances. This challenge is addressed here with two novel mm-wave tolerance-optimized RF concepts in LTCC: load termination and Gysel power splitter. The concept presented here minimizes the effect of fabrication tolerances to provide stable RF response.

Accurate and Process-Tolerant Resistive Load

“…Three test structures are fabricated with a GaN on SiC microstrip monolithic microwave integrated circuit (MMIC) technology and demonstrate that our proposed technique is applicable at the X-band. Studies have shown that the reliability and accuracy of sheet resistance in a fabrication process can be improved to implement accurate loads [12], [13]. However, to the best of our knowledge, this is the first work that obtains a sheet resistance tolerance using an improved design.…”