Epic thermal upgrade for iPhone 18 Pro! Apple A20 Pro uses TSMC WMCM packaging.

According to Fast Technology on July 13, recent leaks of confidential Apple documents have led to the early release of the iPhone 18 Pro, with everything from its appearance to its internal motherboard and chip design being thoroughly exposed.

Document information confirms that the Apple A20 Pro uses TSMC’s WMCM (Wafer-Level Multi-Chip Module) packaging technology, which is significantly different from the current mainstream CoWoS 2.5D packaging and traditional PoP stacking packaging for mobile phones. It can solve the long-standing heat accumulation and memory bandwidth bottlenecks of mobile phone chips from the underlying architecture.

The most significant feature of WMCM technology is that it eliminates the silicon interposer layer and directly lays out the SoC logic die and LPDDR5X memory die horizontally on the same RDL redistribution layer. This significantly shortens the interconnection distance between chips, which not only reduces data transmission latency but also reduces the overall package size, leaving more space for heat dissipation and battery inside the device.

Traditional mobile phone chips generally adopt a PoP structure where memory is stacked on top of the processor. The dual heat sources of computing chip and memory are superimposed, making it difficult for heat to be conducted outward. High-load games and large-scale AI models on the device are prone to heat accumulation, triggering performance throttling.

The WMCM flat layout allows the SoC and memory to each have independent heat dissipation contact surfaces, significantly increasing the overall effective heat dissipation area. This enables stable maintenance of full frame and high computing power output for extended periods, resulting in a significant improvement in sustained performance.

However, this new packaging solution has obvious shortcomings. The wafer-level wiring, die bonding and supporting testing processes are more complex, and the production yield control is more difficult. This will directly increase the overall chip packaging cost. Coupled with the current global memory chip price increase cycle, it will further increase Apple’s hardware procurement expenses.

In addition, the supply chain also revealed that the primary supplier of the LPDDR5X high-speed memory for the A20 Pro is SK Hynix, which leverages its HBM and mobile memory production capacity advantages to ensure supply for Apple’s high-end models.

This new packaging system, combined with TSMC’s 2nm process, will become a core hardware upgrade highlight of the iPhone 18 Pro series, further improving the long-standing issues of high-load heat generation and limited short-term performance release in Apple’s flagship phones.