Integration of RF Circuitry and Liquid Cooling Chamber on LTCC Substrate for Tile TR Module

This paper presents a low temperature cofired ceramic (LTCC) package with radio frequency (RF) circuitry and fluidic chamber. The RF power chips can be arranged closely over the cooling chamber, which provides good heat transfer performance. The fabricated fluidic chamber with a size of 20 mm × 20 mm × 0.4 mm keeps its shape well, inside which a 3 × 3 pin-fin array have been added to improve the thermal and mechanical performance of the LTCC substrate. The RF transmission lines such as CPW and quasi-coaxial vertical transition in LTCC show good RF performance up to 12 GHz, while the LTCC substrate has a low pressure loss of 30.4 kPa at the water flow rate of 330 mL/min, which allows a low pump capacity in the cooling system. The proposed LTCC package shows a promising solution for highly integrated X-/Ku-band tile-type transmitter and receiver (TR) module.