Dielectric Loss and Signal Attenuation
At 5G mmWave frequencies (24GHz - 40GHz), the dielectric properties of insulating tapes become critical. Standard tapes with a high Dissipation Factor (Df) absorb RF energy, converting valuable signal into heat. This causes signal attenuation and reduced range. Low-loss substrates like low-Df polyimide or PTFE are essential.
Shielding Effectiveness at High Frequencies
Standard copper foil tapes may become transparent to high-frequency waves if the foil is too thin (skin depth issues) or if the adhesive creates a standoff distance. Absorber tapes (loaded with magnetic fillers) are often required alongside reflecting foils to suppress cavity resonances inside 5G modules.
Thermal Density Management
5G devices have extreme power densities. Tapes must perform a dual role: electrical insulation and thermal conduction. Standard insulators act as heat blankets, causing chip overheating. Thermally conductive dielectric tapes are necessary to route heat away from RF amplifiers while maintaining electrical isolation.