Low-Loss Commercial Deposition Technology for Thick Ferrites and Ferrite/Insulator Films on Printed Circuit Boards

Integration of RF ferrites on printed circuit boards (PCBs) is highly desired for realizing compact, lightweight and low-cost systems in package (SiP) integrated with different RF components, including compact antennas and antenna arrays, tunable filters, phase shifters, isolators, circulators, etc. However, it has been challenging to integrate ferrite materials on PCBs. Spin spray deposition is a proven and viable method that is able to produce fully dense, high crystalline quality, and low-loss RF ferrites at a low temperature at a low cost. However, spin spray technique and facilities are not commercially available. Two major issues severely limit ferrite integration on PCBs by spin spray deposition: (1) limited ferrite film thickness of 5~10 m, low loss tangent 1GHz on large scale rectangular (2436) PCBs. At the same time, new compact integrated RF ferrite devices, antennas and inductors, will be demonstrated on ferrite coated PCBs.