Yes, that should be "higher" SNR, just as I believe your last question should be "does SNR increase as size shrinks". The trends are to smaller sizes--already die sizes are dipping below 1 mm--but I don't believe scaling is the sole contributor to higher SNR.
According to IHS Knowles is way out front in the top 10 followed by AAC, Invensense (through its acquisition of Analog Device MEMS mic business), Goertek, STMicroelectronics, Hosiden, BSE, Wolfson, Bosch and NeoMEMS.
Its the voice command algorithms that do that magic, but the old "garbage-in garbage-out" rule applies here too, in that the higher definition the MEMS mic, the more accurate will be the recognition of voice commands.
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