IPC TM-650 2.5.5.10

Abstract

This test method describes procedure for measuring dielectric permittivity and loss tangent of embedded passive materials. The measurements are made in an APC-7 coaxial configuration where the test specimen represents a load terminating an air-filled coaxial transmission line. The method is suitable for testing high dielectric constant (high-k) polymer-composite materials having nominal thickness of 1 μm to 300 μm at frequencies of 100 MHz to 12 GHz. With proper use and computation the frequency range can be extended to 18 GHz. Existing measurement methods (see Section 2) assume quasi-static conditions in the thin film specimen, whereas this test method produces meaningful results at frequencies greater than hundreds of megahertz and where high-dielectric constant, thin film materials are to be measured. This test method is for qualification of filled and unfilled, distributed capacitance, thin film materials where the permittivity in the frequency range of 100 MHz to 12 GHz is a critical functional parameter. The method is also applicable to polymer resist materials for embedded passive devices. This method fills a test method gap within the IPC-TM-650 Test Methods Manual for thin film, high-k dielectrics.