Characterization of Liquid Crystal Polymer (LCP) Material and Transmission Lines on LCP Substrates From 30 to 110 GHz

Abstract

Abstract-Liquid crystal polymer (LCP) is a material that has gained attention as a potential high-performance microwave substrate and packaging material. This investigation uses several methods to determine the electrical properties of LCP for millimeter-wave frequencies. Microstrip ring resonators and cavity resonators are measured in order to characterize the dielectric constant ( ) and loss tangent (tan ) of LCP above 30 GHz. The measured dielectric constant is shown to be steady near 3.16, and the loss tangent stays below 0.0049. In addition, various transmission lines are fabricated on different LCP substrate thicknesses and the loss characteristics are given in decibels per centimeter from 2 to 110 GHz. Peak transmission-line losses at 110 GHz vary between 0.88-2.55 dB/cm, depending on the line type and geometry. These results show, for the first time, that LCP has excellent dielectric properties for applications extending through millimeter-wave frequencies.

3d Lumped Components and Miniaturized Bandpass Filter in an Ultra-Thin M-LCP for Sop Applications

“…LCP has many electrical, and mechanical characteristics that make it an excellent candidate for wireless SoP [6]. Its dielectric constant is very stable across a wide frequency and temperature ranges.…”

“…Moreover, its low dielectric constant and loss tangent of 2.9 and 0.0025 respectively, are very suitable for efficient RF and microwave designs. The coefficient of thermal expansion (CTE) of LCP can be engineered between 0 and 40 ppm/ • C [6], which improves its thermal compatibility with wide range of materials including PCBs. The fabrication process of LCP does not involve temperatures above 280 • C. This is very low as compared to (850 ∼ 950) • C which is required for LTCC's fabrication [3].…”

Design and integration of inkjet-printed paper-based UHF components for RFID and ubiquitous sensing applications

“…This is required to isolate the dielectric loss α d since the ring resonator method gives the total loss at the frequency locations of the resonant peaks. The loss tangent is a function of α d (in Nepers/m) according to [1]:…”

“…In this paper, for the first time, the electrical characterization of dielectric constant (ε r ) and loss tangent (tanδ) characterization [1,2] of paper over the frequency range 0.4 GHz to 2.4 GHz has been developed using the microstrip ring resonator method. First, one microstrip line was fabricated on photo paper for the measurement of ε r and tanδ.…”

A curvature CPW-fed ultra-wideband monopole antenna on liquid crystal polymer substrate using flexible characteristic

“…The UWB communication systems require the transmission of pulses instead of modulated sine waves, ultra-wide bandwidth, omni-directional pattern, group delay, constant gain, and a linear phase response [4]. Liquid crystal polymer (LCP) is a relatively new material with excellent properties for use in high frequency circuits due to its low loss and low dielectric constant for mm-wave passive circuit and printed antennas [5]. Furthermore, LCP substrates can be used for multilayer (three-dimensional) modules that can be flexed, rolled up, and deployed for space applications as well as for conformal (e.g.…”