How To Make A CPU

Summary

This video provides a step-by-step guide on how to create a CPU, starting from obtaining raw silicon dioxide from a rock to crafting a monocrystalline silicon wafer. It details the purification processes, including doping, lithography, and various epitaxy techniques, culminating in the production of silicon dies ready for packaging. The explanation highlights the intricate chemical reactions and precision required at each stage, showcasing the complexity of semiconductor manufacturing and the transformation of simple materials into advanced technology.

Takeaways

• 🪨 Start with a rock to obtain concentrated silicon dioxide.
• ⚗️ Purify the silicon dioxide to 99.9% and then to 99.9999999% polysilicon.
• 🔥 Heat polysilicon ingots in a crucible at 1698 °K to create molten silicon.
• 🔬 Use a seed monocrystal to pull out a monocrystal of pure silicon from the molten vat.
• 🔪 Cut the monocrystalline silicon ingot into thin slices to produce silicon wafers.
• 🧪 Dope the silicon wafers with Boron or Phosphorus to modify electrical properties.
• 💡 Apply photoresist on the wafer and use a photo-lithographic mask to control chemical reactions.
• 🧼 Develop the photoresist, etch the wafer, and remove leftover photoresist for a clean surface.
• 🔗 Perform various epitaxy and doping techniques to enhance the silicon structure.
• 💻 Cut the silicon wafer into dies, attach bond wires or use the flip-chip method for electrical connections.

Q & A

What is the first step in making a CPU?

The first step is to get a rock.

What do you do after smashing the rock?

After smashing the rock, you have 98% concentrated silicon dioxide.

What is the goal of purifying silicon dioxide?

The goal is to achieve 99.9999999% polysilicon metal.

At what temperature should the silicon ingots be heated?

The silicon ingots should be heated to 1698 °K.

What is the purpose of dipping a seed monocrystal into molten silicon?

Dipping the seed monocrystal into molten silicon allows it to grow into a pure silicon crystal as it cools.

What is done after cutting the monocrystalline silicon ingot?

After cutting the ingot, you get pristine freshly-cut silicon wafers.

What does doping the silicon wafers involve?

Doping the silicon wafers involves adding elements like Boron or Phosphorus to alter their electrical properties.

What role does the photoresist play in the manufacturing process?

The photoresist is applied to the wafer to create patterns for subsequent chemical reactions.

How does the chromium-etched photo-lithographic quartz mask function?

The mask controls the location of chemical reactions on the silicon wafer by casting shadows when a laser beam is shone through it.

What is the final step in preparing the silicon dies for use?

The final step involves locating the pads on the silicon chip and attaching bond wires or using the flip-chip method for electrical connections.