iPhone 5s: Production problems with Fingerprint chip?

The new iPhone 5s is rumored to contain a Fingerprint sensing chip from the acquired company Authetec. A source told Digitimes that the production of the chip, along with the production of the LCD driver chip, has been facing yield rate problems. The result is that commercial production will not start until late July. According to a report in the International Business Times, the Fingerprint chip design has been the cause of the problems, along with the fact that the chips are made overseas by Apples partner TSMC.