A 10 MHz to 100 GHz LTCC CPW-to-stripline vertical transition

A broadband 50Ω coplanar waveguide (CPW)-to-stripline transition is presented which is capable of operation up to 100 GHz. This vertical transition is fabricated in low-temperature co-fired ceramic (LTCC), and it is appropriate for system in package (SiP) module packaging. It was designed for wafer probing an LTCC module containing an embedded stripline. This compact transition occupies only two layers of nominal 5 mil thick tape. Both simulated and measured s parameter results are shown for back-to-back transitions up to 110 GHz. Measured insertion loss for a single transition is less than 0.3 dB near 60 GHz and less than 1 dB up to 100 GHz.