What is Ultra HDI?
September 22, 2023 | Happy Holden, I-Connect007Estimated reading time: Less than a minute
Ever since high-density interconnect (HDI) was created in 1982 by Hewlett-Packard to package its first 32-bit computer powered by a single chip, it has continued to evolve and provide the solutions for miniaturized products. The leading edge of HDI technology became the process used for organic flip-chip packaging for the semiconductor industry. The two distinct markets—IC substrates and product-system integration—are now colliding and utilizing the same ultra-HDI manufacturing processes (Figure 1).
Introduction
These two markets have different characteristics as well as specifications. The middle ground is currently occupied by the very high-density PCBs called substrate-like PCBs (SLPs).
The differences lie in that IC packaging is for components of unspecified final application while an HDI PCB is the result of a system-integrated product. But time and evolution have introduced a semiconductor component system integration strategy which the IEEE now calls heterogeneous integration.
Reference:
- Inspired by IEEE Heterogeneous Integration Roadmap, Chapter 2, pp 10.
Continue reading this article in the September 2023 issue of PCB007 Magazine.
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