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There are a few very headaches. After studying for a few days, I feel that some logic can't be figured out, so I can only ask expert readers.

1. Production capacity of monocrystalline silicon ingots: The processing time of a 12-inch monocrystalline silicon ingot with a length of 1.5 meters is about 100 hours. What is the approximate amount? If there is no loss, the actual length of single crystal silicon can be pulled up to 6 meters.

The time required is about 400 hours. Excluding work stoppage, cleaning and other work, 600 hours are calculated, which is about 25 days.

The thickness of an inch wafer is about 0.775 mm at the beginning, and it will be thinned to 190 microns or even 150 um after processing and thinning.

What is the approximate diameter of this gold wire?

0.1 mm? So thin, not easy to break?

In other words, the initial thickness required for a wafer is = 0.775 (wafer initial thickness) + 0.1 (diamond wire diameter) = 0.885 mm

6 meters long monocrystalline silicon rod, you can calculate how many wafers can be cut out.

About 6,000 pieces if you don't count cutting pieces?

This data feels a bit exaggerated.

Then, how much is the cost of a 6-meter-long monocrystalline silicon?

How much is it to sell to a chip factory?

Can a single crystal furnace with a power of 10MW be enough?

It is often heard that 100 single crystal furnaces with a power of 10MW are generally required to build 1GW of monocrystalline silicon wafer production capacity.

Generally, the monocrystalline silicon factory is 20GW, that is, 2000 monocrystalline silicon furnaces?

2000 monocrystalline silicon rods per month?

12 million wafers?

The logic of this data is not normal.

The main reason is that this logical problem cannot be figured out.

In general fabs, the monthly production capacity is about tens of thousands of wafers, because processing wafers is too time-consuming, such as grinding is too time-consuming, and it is easy to break.

Of course, wafer processing and the production of monocrystalline silicon rods are two different things.

Ask: Is the production of monocrystalline silicon ingots and wafer processing the same factory?

2 The shipment rate of wafers.

The surface area of ​​a 12-inch wafer is about 70,659 square millimeters, and it is said that the shipment rate is about 65%. Taking Huawei Kirin 990 5G as an example, its chip area is 113.31 square millimeters (as many as 10.3 billion chips are integrated in this small area) Transistors), which can be regarded as the yield rate, can probably ship 300 chips.

With a monthly output of 50,000 pieces, that is 15 million chips, which can satisfy 15 million mobile phones?

Recently, the knowledge of monocrystalline silicon, wafer and chip processing is very swollen, and it is too troublesome to settle accounts.

Maybe I write casually, and most readers can't find mistakes, but I still don't want to be too casual, some things must be rigorous, and I hope you can give me some pointers.

Thanks