Doped, low-temperature co-fired glass-ceramic (LTCC) insulating substrates, and related wiring boards and methods of manufacture

Doped, low-temperature co-fired ceramic (LTCC) insulating substrates and related wiring boards and methods of manufacture are disclosed. The doped, LTCC insulating substrate is formed from a baked (e.g., sintered) glass-ceramic aggregate material formed from a glass material, a ceramic filler material, and a composite oxide. The crystallized glass-ceramic aggregate is then doped with Iron and/or Manganese before baking. Iron or Manganese can further reduce dielectric loss and the loss tangent of the LTCC insulating substrate formed from that glass material. The glass material becomes crystallized due to an oxide crystal phase being deposited on the glass material during baking, which reduces the dielectric losses. This may be important for the application use as wiring boards for high radio-frequency (RF) electrical circuits where low dielectric loss and loss tangent is desired to achieve a desired signal transmission delay performance.