Silicon Wafer Formation and Properties

Silicon Wafer Formation and Properties

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Silicon wafers are produced by high technology silicon wafer manufacturer firms. These companies are able to produce and provide such wafers to most any diameter. They can even be created to be the size of 400 millimeters diameter with ultra flat thickness. Here we will look at the formation and properties of silicon wafers.

The Basics of Silicon Wafers

Wafers refer to thin slices of semiconducting product like a silicon crystal. They are also referred to as substrates or slices. These wafers are employed to fabricate micro-devices like integrated circuits. These wafers prove to be the substrate on which microelectronic devices are constructed.

It takes a great number of micro-fabrication processes to develop them. Some of these are ion implanation, etching, photolithographic patterning, and deposition of the materials. In the end of the process, the wafers will be diced (or separated) and then packaged up for shipping. Solar cells are constructed from these silicon wafers.

Formation of Silicon Wafers

Wafers are developed from almost defect-free crystal material. It must be extremely pure. These wafers come in standard sizes of eight inches, six inches, four inches, and two inches.

One of the primary processes for creating these wafers is called the Czochralski growth. Polish born chemist Jan Czochralski invented the process. This happens when an ingot (in the shape of a cylinder) made from extremely pure monocrystalline seminconductor is crafted through taking out a seed crystal from what is known as a “melt”. The crystals can be transformed into p-type or n-type extrinsic semiconductor crystals by adding in phosphorus or boron, two common impurity atoms. Finally the formed ingot will be sliced down into a wafer utilizing a wire saw, or wafer saw. The slice will then be highly polished to make a wafer.

Silicon Wafer Properties

These wafers come in a wide range of diameters that start at one inch and extend to roughly 18 inches. Such diameters have increased over time to the point that the present day cutting edged factory produces 12 inches as a standard, followed by the 18 inch up and coming size. The plants that fabricate them are called fabs as a moniker. It is the dimensions of the diameter of these silicon wafers that define the factories.