TSMC, the Taiwan Semiconductor Manufacturing Company, has been granted the necessary permission from the Taiwanese government to build a 450mm (almost 18") wafer factory. While the factory was given the go-ahead, the technology to manufacture 450mm wafers isn't quite there. The chairman of TSMC, Morris Chang, said that the technology could be as far as 5 years away.
Essentially what a 450mm wafer factory would do is increase the yields on whatever process is imprinted on the wafer. Currently the 28nm process is what has been the major hurdle. Yields from companies all around have been incredibly low. Back in May it was rumored that NVIDIA was shipping around for other companies because TSMC couldn't meet demand. Most companies can't meet 28nm demand, which is why the 450mm wafer would be beneficial. As demand for the 28nm and smaller processes is expected to grow, TSMC is looking for ways to increase yields.
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