Our bonding film allows multilayer PTFE PCB’s speed up data center servers!

Low-transmission-loss bonding film <AS-400HS>

HomeSolutionLow-transmission-loss bonding film <AS-400HS>
Applicable Business Areas
Semiconductor manufacturers, Substrate manufacturers
Target Applications
Substrate bonding film

Due to the dissemination of IoT, AI and big data, the amount of data to be handled by the next generation data centers is predicted to be dramatically increased, and the demand for large servers capable of transmitting a large amount of data at higher speed has been increasing. Accordingly, a circuit substrate that can be multilayered to support high-capacity, high-speed transmission is needed for use in large data servers.
In such situation, as a multilayer substrate utilizing fluororesin (PTFE) is expected to be used by its excellent low-dielectric properties. However, it is difficult to construct a multilayer using PTFE material as it is necessary to press PTFE under high temperature due to a high melting point of PTFE.
Our low-transmission-loss bonding film <AS-400HS> has an excellent bonding ability with PTFE, allowing to construct a PTFE multilayer under low temperature. This contributes to high-speed transmission of the next generation data center servers.

Innovative Solution

Capable to construct multilayer of PTFE materials with an excellent bonding ability with PTFE, low temperature press conditions

Out of all low-loss materials, PTFE is known as the lowest transmission-loss, but costly material.

Although it is necessary to press PTFE materials at a high temperature above its melting point (327℃), almost no other laminate material can endure such high temperature, thereby difficult to multilayer with other materials.

Our low-transmission-loss bonding film <AS-400HS> has high toughness and self-assembles functional groups having strong interaction with fluorine atoms on the interface of the film, thereby providing an excellent bonding ability with PTFE. Therefore, using <AS-400HS> as a bonding film, it allows to go through complex multilayer process under low temperature (200℃), offering a lower cost, higher-speed solution.

Cross-section of the multilayer of PTFE material with <AS-400HS>
Interface between <AS-400HS> and PTFE (magnified)
Bonding ability of <AS-400HS> with various PTFE materials

Core materials

PTFE w/Ceramic

PTFE w/o filler

PTFE w/glass cloth

Adhesive (Peeling)

Failure of PTFE itself
(No failure between PTFE and AS-400HS)

Failure of PTFE itself
(No failure between PTFE and AS-400HS)

Failure of PTFE itself
(No failure between PTFE and AS-400HS)

Product Features

Excellent low dielectric characteristics

<AS-400HS> has low dielectric properties (Dk = 3.0, Df = 0.0023) which maintains low loss characteristics of PTFE substrates. Furthermore, with its excellent bonding ability, low profile copper foil is used to reduce transmission loss to -0.58 dB/cm (at 76 GHz).

Transmission loss comparison of <AS-400HS> and other materials

Superior laser processability

Due to superior laser processability, small via holes can be created.

Laser processability of <AS-400HS>

High-density circuit boards can be designed

As <AS-400HS> is a thermosetting resin, it is possible to sequentially laminate and ensure interlayer connectivity. Small via holes can be processed at different positions in each layer, capable for high-density circuit board design.