High Tg PCB

Amorphous plastics transition from a glassy or rigid state to a rubbery, soft state at a certain temperature when heated. This point is called glass transition temperature (Tg). The Tg depends on the polymer’s mechanical properties, such as tensile strength and impact resistance. Such substrates have been instrumental in making PCBs for high-frequency and high-temperature applications. At PCB YOU, we offer high Tg PCBs tailored to your specific needs, using various popular Tg materials. Our generic high Tg PCBs can withstand temperatures as high as 180 degrees Celsius.

High-Tg PCBs require materials with a Tg value above 150 degrees Celsius, which is significantly higher than the regular FR4 substrates' values around 120 degrees Celsius. The material's Tg value must be at least 20 degrees higher than the device or system's operating temperature. We use Tg materials made and standardized by reputed players such as Rogers, Nelco, Tectonic, Ventec, Isola, and more. Here are some of them.

Here’s an overview of our high Tg PCB fabrication process.

• We choose the right high Tg material based on its mechanical, thermal, and other properties vis-à-vis your application requirements.
• This design file is converted into a fabricated board, which is then validated through testing.
• We run through DFM checks to identify and avert potential errors.
• The files are then fed to CAM software to get the right images, layer formats, drilling data, and more.
• The generated CAM output files are necessary for manufacturing as they include the IPC netlist, drill program, solder masking details, and more.
• Next, inner layer imaging, which involves circuit patterning, is done using a laser for utmost precision as most components are miniature in size.
• The next step is etching, wherein excess copper is removed from the laminate foil.
• Now all the layers are inspected using AOI. Next is the lamination process, where copper foil, prepreg layers, and inner cores are bonded to form a stackup under controlled temperature. This forms a multilayered board.
• Next, holes are laser drilled to create vias and solder leaded components. However, this can produce burrs, so we carry out the deburring process.
• Then copper plating is applied to hole walls and surfaces to make them conductive. This is done through electroless copper deposition.
• Next, outer layers are etched using photoresist, wherein a layer of it is applied evenly over the cleaned panel.
• Copper electroplating is done to ensure conductivity between the PCB layers.
• Once the panel plating is done, the photoresist layer is removed.
• Next, we apply solder mask to ensure insulation and distinguish between solderable and non-solderable areas.
• Surface finishing and silkscreen are the next two steps.
• Now the board is tested for open and short traces using flying probe testing.
• Routing and v-scoring are the final steps of the PCB manufacturing process, wherein the boards are profiled and cut out of the production panel using a V-scoring machine.

We are particularly focused on quality and have a stringent testing process in place. Since, high Tg PCBs are mainly used for high-frequency applications, there are several miniature-sized components. They find use in mission-critical applications in aerospace, defense, and medical sectors as well as high-temperature applications. We use automated testing methods such as automated optical inspection, functional testing such as flying probe, x-ray inspection, and test fixtures.

High Tg PCBs help improve the dimensional stability and thermal properties of your product or system. The low thermal expansion coefficient and high resistance to thermal stress. We help you choose the right PCB material based on your Tg value requirements. You can totally rely on us in terms of accuracy and precision. At PCB YOU, we have a skilled team and the required expertise to help you meet the most complex requirements involving a high Tg PCB assembly. If you need any further information on our high Tg materials, custom options, or want to share your requirements, feel free to contact us via phone or email.