A: A common concern with PTFE-based laminates is that its dielectric constant varies with temperature. There are different transition points to the molecular geometry of PTFE, with the 2nd order phase change at 19°C. Through its composition, Arlon’s CLTE achieves near zero dielectric constant change across temperature, including 19°C. This is important to military, defense and satellite electronic applications, where CLTE’s mechanical stability and very low CTE are also important for insuring device reliability. In addition, independent tests show Arlon CLTE has the lowest insertion loss in its class. Some competitive products claim lower loss tangent in controlled laboratory tests, however in the field, we have found that CLTE offers superior performance and have seen 10% to 50% lower insertion loss at microwave frequencies. We believe these results for CLTE are in part due to its lower moisture absorption, better resistance to wicking of processing chemicals and lower conductive loss. Utilization of special low profile copper combined with our unique formulation, provides lower conductive loss, while still providing excellent copper bond. CLTE is also commonly found in multi-layer boards and is uniquely designed with a matching thermoplastic bonding film, CLTE-P. The product was successfully used in the Globalstar satellite, which employed a 68 layer antenna array beamforming network built on CLTE.
Additional information is available on Arlon’s website at www.arlon-med.com or you can contact Arlon technical support by phone at 800-635-9333. |
