Wafer size

• larger wafers are used presently because the cost per wafer remains basically the same for small and large wafers, thus the cost per die gets smaller if we can put more dies on the same wafer.

 3 inch         76 mm

 4 inch       100 mm

 5 inch       125 mm

 6 inch       150 mm

 8 inch       200 mm

12 inch      300 mm

16 inch      400 mm            2.54 cm = 1 inch

 

Other properties

• Mechanical specifications
  • Type of crystal growth (CZ, FZ, epitaxial)
  • Thickness - (they might break if too thin)
  • Bow - a concavity appears due to sawing
• Chemical properties/Surface
  • Oxygen and carbon content - important for some applications (ICs)
  • Flatness - important for small devices