TSMC will begin volume production of 5nm-based A14 chips for iPhone 12 models in April, according to industry sources cited by DigiTimes. A-series chip production usually begins around April-May, so the process appears to be on schedule.

A10 chip: 16nm

A11 chip: 10nm

A12 chip: 7nm

A13 chip: 7nm+

A14 chip: 5nm expected

TSMC has been Apple's exclusive supplier of A-series chips since 2016, and its chips have gradually become smaller as it continues to refine its manufacturing process, benefitting performance, battery life, and thermal management on iPhones.

Last year, TSMC announced a $25 billion investment in its new 5nm node technology in a bid to remain Apple's exclusive supplier of processors.

Apple plans to introduce four high-end iPhone 12 models with 5G support in the fall, including one 5.4-inch model, two 6.1-inch models, and one 6.7-inch model, according to analyst Ming-Chi Kuo. A new lower-end iPhone is also widely rumored to launch in the first half of 2020, but it is expected to have an A13 chip.