Thin‐film embedded resistor and capacitor technologies

Printed circuit board designers face formidable challenges of increased functionality in smaller size boards, and reduced EMI in high‐speed circuits. Embedded passives technology can open up valuable space on the board surface while also improving the electrical performance and reliability of high density, high‐speed designs. Shipley has developed a thin‐film, high sheet resistivity (1,000 Ω/□) resistor material sold under the trade name InSite™ in response to this market need. This paper describes the manufacturing process for embedded resistors and discusses measured data on resistance values, uniformity, and thermal effects, and their impact on design rules for resistor size. Preliminary results of Shipley's thin‐film embedded capacitor technology with high capacitance densities (10 and 200 nF/cm 2 ) are also presented.