Experimental verification of the use of metal filled via hole fences for crosstalk control of microstrip lines in LTCC packages

Coupling between microstrip lines in dense RF packages is a common problem that degrades circuit performance. Prior three-dimensional-finite element m ethod (S-D-FEM) electromagnetic simulations have shown that metal filled vi a hole fences between two adjacent microstrip lines actually increases coup ling between the lines; however, if the top of the via posts are connected by a metal strip, coupling is reduced, In this paper, experimental verifica tion of the 3-D-FEM simulations is demonstrated for commercially fabricated low temperature cofired ceramic (LTCC) packages. In addition, measured att enuation of microstrip lines surrounded by the shielding structures is pres ented and shows that shielding structures do not change the attenuation cha racteristics of the line.