Analysis of Differential Crosstalk and Transmission for Via Arrays in Low Temperature Cofired Ceramics

Abstract

Given the ubiquitous use of via arrays in multilayer substrates based on organic materials, this work explores ceramic-based solutions instead. Assuming typical design and technology constraints, the performance of via arrays on low temperature cofired ceramics is studied in terms of crosstalk as well as transmission. Both single-ended and differential signaling are considered, thus covering a broad range of use cases for microwave applications and high-speed digital links. By employing single vias optimized with respect to 50Ω systems as fundamental building blocks for larger via arrays, different array configurations are proposed and analyzed. The question as to what moving from organic to ceramic materials and vice versa implies in terms of electrical performance is investigated. The majority of the work is based on the computationally efficient physics-based via modeling technique due to the size and complexity of the via array models, but comparisons to conventional full-wave solvers show strong agreement between the two methods up to 50GHz.