Wall?Still Jingfang?How To Calculate CVD Diamond Wafer Size

In the past impression, the wafer was round and the chip was square.

Why is it called a wafer?Not called Jingfang?Why is the wafer round and the chip is square?How to calculate the size of the wafer?Nympho

Yesterday, Ningbo Crystal Diamond60 mm × 60 mmThe single crystal diamond chip caused heat and discussion in the industry. This is3.35inch?still2.36inch?In the industryWhat is the standard?

Before you figure out this size, we first understand why the chip is square and the wafer is round?

   Why is the wafer round and the chip is square?

This is determined by the production process.

At present, mainstream semiconductor materials are also silicon semiconductors.Silicon wafers are cut on cylindrical silicon rods, so the cross section can only be circular.

It can be understood as specific.(seed)Rotary to grow.Polycrystal silicon is melted and put a 坩埚(Quartz Crucible)In the middle, put the seed crystal in the pimple and rotate at a constant speed and pull it up.(ingot)EssenceThis method is always used nowCZLaw(Czochralski), Also called the single crystal straight pull method.Then the silicon ingot is then cut into silicon tape through the diamond line.So the cross section can only be round.In other words, the rotation of the rotation of the single crystal straight -pulling process determines the cylindrical type of the silicon ingot, which determines that the wafer is round.

But in daily life, the chips we see are all square. When making chips on round wafers, there will always be some areas that are not available.So why can't you use square wafers to increase utilization?

During the manufacturing process, wafers need to go through multiple steps, including sedimentation, lithography, etching, etc.These steps are usually carried out based on rotary motion, while the rotation movement of circular wafers is more stable and uniform, which is conducive to maintaining the accuracy and consistency of the manufacturing process.

But why is the chip?In fact, round chips are actually more difficult to make!

After the steps of the silicon wafers are coated, light, etching, ion injection and other steps, they will be manufactured one by one. However, the chip is still on the wafer at this time.Solid chip.The square chip can be cut all by only a few knives.What if it is a round chip?It takes a few times more time to cut it.From the direction of packaging, the square chip is easy to perform lead operations, even if it isFlip chipThe type package, the square is more convenient for the machine to operate the chip willI/OThe interface is aligned with the pad.

The most important point is that round chips do not solve the problem of waste of silicon wafers.Cut many square areas on a wafer, there will be no gaps in the middle of these areas, leaving only space on the edge of the wafer.However, if many circular areas are cut from a plane, some areas will definitely be wasted in the middle, and at the same time, it is not possible to avoid waste from the periphery of the wafer.In fact, saving wafer area is always an important issue.The more chips that can be produced on the wafer, the higher the production efficiency and the lower the cost of a single chip.The best way to solve production efficiency is to improve the wafer area.From the perspective of wafer utilization, it is impossible to have round chips.

Then the problem is here again,CVDIs the diamond chip, which is called the wafer?Still Jingfang?

At present, microwave plasma chemical gas deposition (MPCVD) As the best way to prepare large -scale, high -quality monocrystalline diamond.Vajra chips produced by homogeneity are all square.Is this a wafer, or is it a crystal?

   CVDHow to calculate the size of diamond wafer?

Wall, also known as waferswafer, Its size is usually expressed in diameter, and the common size is1inch(25Millimeter)、2inch(51Millimeter)、3inch(76Millimeter)、4inch(100Millimeter)、4.9inch(125Millimeter)、150Millimeter(5.9Inch, usually called6inch)、200Millimeter(7.9Inch, usually called8inch)、300Millimeter(11.8Inch, usually called12inch)and450Millimeter(17.7inch) 。

We generally measure the size of the items with length, width, and height, but how to calculate the size of the square crystal material?Xiaobian also asked industry experts. At present, the diagonal size is usually taken.

This calculation method is suitable for electronic products, such as mobile phones, desktop computers, tablet computers, laptops, LCD TVs, and so on.Our method of measure the size of the screen refers to the length between the two diagonal lines of the screen, and the unit is inch (1inch=2.54centimeter).

According to this calculation rules, for this in the figure60.4mmThe single crystal diamond chip, its wafer size can be calculated like this:

So it was reported by Ningbo Jing Diamond yesterday60 mm × 60 mmSingle crystal diamond chip,3.35The inches is no problem!

So,2024In the year, the size of the single crystal diamond will break through the international single crystal diamond4-5Is it inch?Let's wait and see!