Let's take a 4-inch monocrystalline silicon wafer as an example:
As shown above:
Orientation: <100> indicates the crystallographic orientation of the silicon wafer. This orientation has an important impact on the electronic properties and manufacturing process of the devices on the wafer.
Type: P (Boron) with one primary flat means that the wafer is P-type silicon, that is, it is doped with boron to create excess holes. "one primary flat" refers to the shape of the edge of the wafer, which helps to identify the direction of the crystal lattice.
Resistance: 1-10 Ohm-cm is the resistivity of the wafer.
Grade: Prime / CZ Virgin indicates the quality and purity of the silicon wafer. "Prime" is the highest grade and is used for high-precision applications; "CZ" refers to single-crystal silicon wafers produced by the CZ method.
Coating: None, native oxide only means that there is no additional film layer on the surface of the wafer, only a naturally formed silicon dioxide layer.
Thickness: 525µm (+/- 20µm) is the thickness of the wafer, and the error is controlled within plus or minus 20 microns. Thickness uniformity is critical for subsequent processing steps.
Diameter: 100mm specifies the diameter of the wafer.
Warp: <=30µm, the lower the warp, the better the wafer quality.
Bowing: <=30µm, similar to warping, it is also a measure of wafer flatness.
Main positioning edge: 32.5 +/- 2.5mm indicates the length of the main positioning edge of the wafer, which is used to locate the direction of the wafer. Some wafers also have secondary positioning edges, as shown below:
Surface roughness: 0.2 - 0.3nm, polished one side means that the silicon wafer is a single-polished silicon wafer and the unit of surface roughness is nanometers.
