Demand for Apple's iPhone 5S could outweigh supplies due to fingerprint sensor shortages. Production of the new iPhone has allegedly been limited to three to four million units in the third quarter as a result of the shortages.

The iPhone 5S, which is expected to be unveiled on 10 September, is reportedly set to have a fingerprint sensor built-in to the Home button to improve security.

 

In order to accommodate the fingerprint sensor, KGI analyst Ming-Chi Kuo says that Apple will use a convex Home button made from scratch-resistant sapphire.

However, according to Digitimes, the fingerprint sensor is causing problems for Apple, and could mean a limited supply of iPhone 5S units upon launch.

The report cites "industry sources" who claim that Apple originally planned to produce 10 million units of the iPhone 5S before launch, but that issues with production of the fingerprint sensors has meant that initial shipments of the smartphone could be just three or four million in quarter three of 2013.

Digitimes' sources say that Taiwan Semiconductor Manufacturing Company (TSMC) was scheduled to begin mass production of the fingerprint sensors in May, but that delays have occurred due to "issues related to integration between iOS 7 and fingerprint chips" as well as "a low yield rate at packaging firm Xintec."

According to the report, Apple and TSMC have sent engineers to Xintec to help ramp up the yield rate, and volume production of the fingerprint sensors will kick off at the end of August.

This is not the first time we've heard reports that the fingerprint sensor is causing problems for Apple's new iPhone. In July, Digitimes reported similar concerns, and, in April, Kuo said that the planned fingerprint sensor poses multiple technical challenges that could cause delays.

The good news is that production of the iPhone 5S is expected to increase to 28-30 million units in the fourth quarter of 2013.

See also:

How to fix broken iPhone Home button

How to speed up a slow iPhone 4, iPhone 3GS or other older iPhone handset

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