ABSTRACT

This chapter discusses some of the basics of multilayer design, and the key material and process considerations unique to multilayer low-temperature cofired ceramics (LTCC) design. It provides a first-order estimate based on nominal values of impedance-determining properties, and describes design and worst-case tolerance for single-conductor interconnections. Impedance is the electrical property defined as the total opposition a device or circuit offers to the flow of an alternating current at a given frequency. To be able to integrate and use ceramics as substrates for the electrical circuits, the reader should be aware of the properties of these materials that make them useful for such applications. Conductor geometry in ceramic technology varies with the patterning method and processing. In LTCC technology, capacitors and resistors can be buried in a multilayer structure resulting in high density, improved electrical performance, and improved reliability over surface mount technology components.