Infineon manufactures the 1014, the second microphone in the handset. The giant chip maker is a relatively new entrant into the MEMS market, which was dominated by startup companies until about a year ago.
The industry underwent a lot of change recently, as MEMS devices have gone mass market. Large manufacturers like Infineon have started making MEMS microphones and Akustica (one of the original startups) has been acquired by Bosch.
The Infineon unit looks quite similar to the Knowles unit externally. Yet, each company works their own magic on the inside.