Weave Specification
A spread-glass fabric with a balanced yarn count provides a uniform substrate for high-frequency circuit boards. Utilizing fabric style 1078 improves the consistency of the dielectric constant by minimizing the gaps between glass bundles. This style uses flattened yarns to create a smoother surface for copper cladding or prepreg layers.
It is a preferred choice for designs requiring tight impedance control.
Signal Advantage
Timing differences between signals in a differential pair are reduced when the underlying glass weave is dense and flat. The fabric style 1078 allows signals to travel over a nearly continuous glass surface. It helps prevent the skew that occurs when one trace sits on glass and the other sits on resin.
This benefit is significant for data rates exceeding 10 Gbps.
Manufacturing Integration
Resin encapsulation of the glass filaments is more efficient in spread-weave patterns compared to traditional open weaves. When fabric style 1078 is used in prepregs, it supports the creation of very thin dielectric layers with high breakdown voltages. Laser microvia drilling is more predictable because the laser encounters a uniform material density.
This leads to better hole quality and higher reliability of the plated interconnects. The material is compatible with standard FR-4 processing and high-speed low-loss resin systems.
