RLC effects in fine pitch anisotropic conductive film connections

Resistance, capacitance and inductance of Anisotropic Conductive Films (ACFs) connections determine their high frequency electrical characteristics. The presence of capacitance and inductance in the ACF joint contributes time delay and crosstalk noise as well as simultaneous switching noise (SSN) into the circuit system. Experiments on the transient response of the ACF joint and proposed ACF model were made in order to quantify the amounts of the capacitance (C) and inductance (L) of the ACF connection. Tektronix TDS 3014 Digital Oscilloscope was introduced to measure the transient response, which is typical RLC instant response in the range of ns. PCB board was designed to amplify current signals. An ACF connection equivalent model that consists of resistors, inductor, and capacitor between the planes was adopted from its physical entity. To work out the C and the L from the responses, Kirchhoff's Voltage Law was applied. In conclusion, R, L, and C can be calculated from the equation of RLC transient response, also this paper will explain the RLC effects on the high frequency electrical characteristics of the ACF connection.