Abstract: 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.

Abstract: The present invention describes processes for forming waveguides (200) using multiple co-planar layers of LTCC substrates (212, 212a, 212b). Registration holes (222) on the substrates help align layering of the substrates. An array 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.

Abstract: A method of screen printing on low temperature co-fired ceramic (LTCC) is disclosed that comprises the steps of (i) aligning tape position on the printer table of a screen printer machine for precisely positioning the tape relative to the screen mesh of the screen having a plurality of pattern openings; (ii) adjusting screen printing parameter for setting a printing condition, wherein the squeegee speed is adjusted to 50-100 mm/s; squeegee pressure is 0.05-0.wopa15 MPa; and a gap between the screen and the tape is 0.8-1.0 mm; and (iii) optimizing the screen mesh parameter with stainless steel screen mesh, wherein the screen mesh of the screen is optimized at mesh tension of 22-28 N/cm; mesh angle of 22.5°; thickness of an emulsion of 0.044 mm; mesh wire diameter of 0.028 mm; and screen mesh count of 325 apertures per inch.

Abstract: The present disclosure relates to a multi-layered low temperature co-fired ceramic (LTCC) system on package (SoP) for a millimeter wave optical receiver comprising a top layer, a plurality of first intermediate layers, a plurality of second intermediate layers, and a bottom layer. The top layer further comprises a matching network, passive components, and a signal line disposed on a substrate material, the plurality of first intermediate layers further comprises active amplification components, via holes and a plurality of inner grounding planes that are respectively disposed on a first plurality of LTCC substrates, the plurality of second intermediate layers further comprises a plurality of grounding planes that are respectively disposed on a second plurality of LTCC substrates; and the bottom layer further comprises a grounding plane that is disposed on the bottom surface of the second plurality of LTCC substrates. A method of fabricating the multi-layered LTCC SoP is also described.

Abstract: A method of screen printing on low temperature co-fired ceramic (LTCC) is disclosed that comprises the steps of (i) aligning tape position on the printer table of a screen printer machine for precisely positioning the tape relative to the screen mesh of the screen having a plurality of pattern openings; (ii) adjusting screen printing parameter for setting a printing condition, wherein the squeegee speed is adjusted to 50-100 mm/s; squeegee pressure is 0.05-0.wopa15 MPa; and a gap between the screen and the tape is 0.8-1.0 mm; and (iii) optimizing the screen mesh parameter with stainless steel screen mesh, wherein the screen mesh of the screen is optimized at mesh tension of 22-28 N/cm; mesh angle of 22.5°; thickness of an emulsion of 0.044 mm; mesh wire diameter of 0.028 mm; and screen mesh count of 325 apertures per inch.