Problem with strong return loss in LTCC DC block capacitor

[somf0872]

LTCC DC block capacitor

Hello,

I am designing DC block capacitor in LTCC that can able to surpass till 50 GHz. But the problem is strong return loss at the frequencies greater than 10 GHz. I am trying to accomplish this with Interdigital capacitor technique. Does anybody have idea regarding to eliminate this problem?

--->CÄP<---

 

[DJ]

Re: LTCC DC block capacitor

MIM capacitor can work. Tune the capacitor dimensions. If the capacitor is too large in dimensions then its resonants.

 

[somf0872]

Re: LTCC DC block capacitor

I guess I didn't got u perfectly!

Interdigital capacitor uses the same strategy of having Metal-LTCC Tape(Dupont 943)-Metal but it is in Multilayer(benefits of LTCC) to reduce the total covered area of metallic plate on a single tape.

Reducing the dimesion of metallic strip improves S21 but at the cost of S11 i.e. great return loss (not a perfect DC blocking element).

--->CÄP<---