300 mm is correct. It refers to the wafer size. https://en.wikipedia.org/wiki/Wafer_(electronics)#Standard_wafer_sizes https://en.wikipedia.org/wiki/Wafer_(ele

300 mm is correct. It refers to the wafer size. https://en.wikipedia.org/wiki/Wafer_(electronics)#Standard_wafer_sizes https://en.wikipedia.org/wiki/Wafer_(electronics)#Standard_w...