Processes for forming waveguides using LTCC substrates

摘要

Processes for forming waveguides (200) using multiple co-planar layers of LTCC substrates (212, 212a, 212b) are described. Registration holes (222) on the substrates help align layering of the substrates. Arrays of circuit patterns are printed on each substrate, with each circuit being made up of conductor pattern (213) and/or via holes (224). Cavity alignment holes (226) formed around a periphery of each circuit allow alignment marks to be printed on the substrates for vision inspection. Similarly, circuit orientation holes (227) associated with each circuit allow orientation marks to be printed on the substrates to identify orientation of circuits in each finally formed waveguide. Substrate orientation holes (225) allow marks to be printed on one side of each substrate for alignment during screen printing. These in-process vision inspections and quality assurance tests allow product quality and process yields to improve.

主权项

1. A process for forming a waveguide using multiple layers of low temperature co-fired ceramic (LTCC) substrates and screen printing, the process comprising:
forming a screen printing mask to comprise registration openings that correspond to a predetermined number of spaced apart registration holes located on each of the multiple layers of LTCC substrates; placing the screen printing mask over each LTCC substrate and adjusting a printing table of an associated screen printing machine so that the registration openings on the printing mask align with the corresponding spaced apart registration holes on the LTCC substrate; printing circuit patterns by passing and depositing conductor paste through the screen printing mask onto each of the LTCC substrate, and allowing the printed conductor paste to dry in an oven; and stacking up multiple layers of the LTCC substrates with printed circuit patterns by building layers of the LTCC substrates on a stacking machine, wherein registration pins in the stacking machine align the registration holes on separate layers of the LTCC substrates with one another.