Apple’s new M1 Ultra chips use advances in a kind of chipmaking called “packaging.” The company’s UltraFusion, the name of its packaging technology, links two M1 Max chips with 10,000 wires that can carry 2.5 terabytes of data per second. The process is part of a growing revolution in chip packaging. “Advanced packaging is an important and emerging area of microelectronics,” Janos Veres, the director of engineering at NextFlex, a consortium that works to advance manufacturing of printed flexible electronics, told Lifewire in an email interview. “It is typically about integrating different die level components such as analog, digital, or even optoelectronic “chiplets” within a complex package.”

A Chip Sandwich

Apple built its new M1 Ultra chip by combining two M1 Max chips using UltraFusion, its custom-built packaging method. Usually, chip manufacturers boost performance by connecting two chips through a motherboard, which typically brings significant trade-offs, including increased latency, reduced bandwidth, and increased power consumption. Apple took a different approach with UltraFusion that uses a silicon interposer that connects the chips across more than 10,000 signals, providing an increased 2.5TB/s of low latency, inter-processor bandwidth.  This technique enables the M1 Ultra to behave and be recognized by software as one chip, so developers don’t need to rewrite code to take advantage of its performance. “By connecting two M1 Max dies with our UltraFusion packaging architecture, we’re able to scale Apple silicon to unprecedented new heights,” Johny Srouji, Apple’s senior vice president of Hardware Technologies, said in a news release. “With its powerful CPU, massive GPU, incredible Neural Engine, ProRes hardware acceleration, and huge amount of unified memory, M1 Ultra completes the M1 family as the world’s most powerful and capable chip for a personal computer.” Thanks to the new packaging design, the M1 Ultra features a 20-core CPU with 16 high-performance cores and four high-efficiency cores. Apple claims the chip delivers 90 percent higher multi-threaded performance than the fastest available 16-core PC desktop chip in the same power envelope.  The new chip is also more efficient than its competitors, claims Apple. The M1 Ultra reaches the PC chip’s peak performance using 100 fewer watts, meaning less energy is consumed, and fans run quietly, even with demanding apps.

Power in Numbers

Apple isn’t the only company exploring new ways to package chips. AMD revealed at Computex 2021 a packaging technology that stacks small chips on top of each other, called 3D packaging. The first chips using the technology will be the Ryzen 7 5800X3D gaming PC chips expected later this year. AMD’s approach, called 3D V-Cache, bonds high-speed memory chips into a processor complex for a 15% performance boost.  Innovations in chip packaging could lead to new kinds of gadgets that are flatter and more flexible than those currently available. One area seeing progress is printed circuit boards (PCBs), Veres said. The intersection of advanced packaging and advanced PCB could lead to “System Level Packaging” PCBs with embedded components, eliminating discrete components like resistors and capacitors. New chip fabrication techniques will lead to “flat electronics, origami electronics, and electronics that can be crushed and crumbled,” Veres said. “The ultimate goal will be to eliminate the distinction between package, circuit board, and system altogether.” New chip packaging techniques stick together different semiconductor components with passive parts, Tobias Gotschke, Senior Project Manager New Venture at SCHOTT, which makes circuit board components, said in an email interview with Lifewire. This approach can reduce system size, increase performance, handle large thermal loads, and reduce costs. SCHOTT sells materials that allow the manufacture of glass circuit boards. “This will enable more powerful packages with larger yield and tighter manufacturing tolerances and will result in smaller, eco-friendly chips with reduced power consumptions,” Gotschke said.