Affected by the epidemic, terminal markets such as the Internet of Things and automotive electronics are in strong demand, and the global 8-inch wafer generation. The production capacity is full of capacity, the production capacity continues to be tight, and the "core shortage" incident is well known.

Wafer is composed of pure silicon (Si). A silicon wafer is a round silicon wafer with a thickness of about 1mm (mm) or less. It is generally divided into 6 inches, 8 inches and 12 inches. The wafer diameters are divided into three types: 150mm, 300mm and 450mm. At present, the domestic wafer production lines are mainly 8 inches and 12 inches.

At present, chips with a process of 14nm or below are all manufactured with 12-inch wafers, because the larger the wafer, the lower the substrate cost. From the current data, the shipment area of ​​12-inch wafers accounts for about 65% of the total semiconductor silicon wafer shipment area, and 8-inch wafers account for about 20%. If a 12-inch wafer is used to make chips, how many chips can one wafer produce?

The surface area of ​​a 12-inch wafer is approximately 70,659 square millimeters. But because the chip is square and the wafer is round, there must be leftovers, so the chip on the wafer can actually be regarded as the collection of all the squares that the circle can accommodate. The area of ​​the wafer The number of chips that can be accommodated varies greatly depending on the size. Generally speaking, chips below 14nm are basically made of 12-inch wafers, and a piece of such a wafer can cut about 500 chips that meet the standard of good quality. Taking TSMC as an example, if it produces 1 million wafers per month, it can also produce 500 million chips.