Collaborating Across the Industry

The High Density Packaging User Group drives innovation through active partnerships.
by Tyler Hanes

For more than 30 years, the High Density Packaging User Group has facilitated innovations in the electronics industry supply chain, encouraging collaboration to solve some of the industry’s critical problems.

We sat down with HDP project facilitator Karl Sauter during PCB West 2024 to learn more about the group and some of its ongoing and completed projects.

Sauter said the group’s primary focus is to permit companies to collaborate on large joint research projects that would otherwise be too costly or require too many resources for a single company to conduct independently.

Many large OEMs are not as vertically integrated as they once were, so conducting a research project that goes up and down the supply chain often requires working with multiple companies along each step, he added.

One recently completed project led by Intel looked at the effects of different materials, copper densities and manufacturing processes on coplanarity to minimize variation under large BGAs. Eight laminate manufacturers supplied material samples as part of the study.

Other ongoing projects include looks at improved copper surface roughness modeling, defects and anomalies in backdrilled vias, improving microvia reliability, low-loss materials and copper foils, as well as improving SIR test methods.

The results of projects are shared among members, but HDP periodically publishes its findings in academic papers, with the aforementioned project led by Intel winning IPC Apex’s Best Paper Award in March.

Other completed projects this year included a noncontact foil profile project that brought together 10 copper foil manufacturers and three laser microscope manufacturers to complete statistically significant testing to enable measurement standards and ultra-low profile foil classifications, as well as a thermal analysis methodology evaluation that highlighted the need for a better understanding of test methods and potential improvements required when analyzing next-generation PCB materials.

Some of the group’s ongoing projects are examining the measurement of copper surface thickness and examining the coefficient of thermal expansion and how temperature affects expansion across the X and Y axes, Sauter said.

A Fine-Tuned Process

With its decades of experience in the field, HDP has fine-tuned its process for defining projects and seeing them through to completion. Each project starts in the idea phase, in which members and nonmembers can voice their proposals to determine if there is sufficient interest.

If interest is sufficient, the project moves to the definition phase, in which HDP gathers as much information as possible from members and across the industry to develop a project plan, choose a project leader, finalize its scope and timeline and secure resources, and under the implementation phase, the project is conducted by members.

This approach allows participation of all members who may be interested, and it ensures members are not committing resources to a nonviable project, Sauter said.

“Research always has some risk, and we try to make sure that at every point, we can kill the project early if it should be killed,” he said. “As resources get committed to a project, we have to maximize the chance of success.”

HDP currently has around 50 members, including large OEMs, material suppliers and test facilities, and having a mix of companies that specialize in different areas is important to ensure research stays up to date.

“You don’t have to be a major OEM to be a member,” he said. “You can be a supplier, you can be a test facility, and you will get visibility from participating in the projects.”

Membership also has its privileges, such as sharing the often substantial costs of conducting research, whether it’s adding new equipment or technology, and the results of a project are disseminated only among members, Sauter said.

“We don’t publicly share all the results,” he said. “But quite often, we do want the industry to know that there’s a better way. They may not know exactly how to get there, but it’s of interest for our membership to let the industry know that there’s a better way.”

Sauter said the group has historically targeted around 50 active members but is always looking for potential new members as technology advances into new territories and the industry landscape changes through consolidations and mergers.

“We’re open for new members and we do have areas of technology that we’re looking to work toward,” he said.

He said the industry continues to see growing interest in HDI and ultra-HDI, and the group has a large enough presence that some members encourage their suppliers to join and add to the effort of tackling some of the challenges they are seeing.

Other areas of interest among members include new substrate materials and packaging innovations, Sauter said. While there may not be active projects in those areas, companies can encourage new members and new research directions.

“It may not be something that’s currently covered, but they want good research done and want to collaborate,” he said. “They can join and have joint research done and see the new ideas. Our value-add is to improve the entire industry.”

Tyler Hanes is managing editor of PCD&F/CIRCUITS ASSEMBLY; tyler@pcea.net.