Sorry for the two ''f'' (wafer).

The difficult and costly 300 mm process only accounted for approximately 20% of worldwide capacity on a wafer area basis by the end of 2005.[17] The step up to 300 mm required a major change from the past, with fully automated factories using 300 mm wafers versus barely automated factories for the 200 mm wafers.

• 1-inch (25 mm)
• 2-inch (51 mm). Thickness 275µm.
• 3-inch (76 mm). Thickness 375 µm.
• 4-inch (100 mm). Thickness 525 µm.
• 5-inch (130 mm) or 125 mm (4.9 inch). Thickness 625 µm.
• 150 mm (5.9 inch, usually referred to as "6 inch"). Thickness 675 µm.
• 200 mm (7.9 inch, usually referred to as "8 inch"). Thickness 725 µm.
• 300 mm (11.8 inch, usually referred to as "12 inch"). Thickness 775 µm.
• 450 mm(17.7 inch, usually referred to as "18 inch"). Thickness 925 µm (expected).[13]

http://en.wikipedia.org/wiki/Wafer_(electronics)