Knowledge

2-24.Wafer Orientation

2-24.Wafer Orientation Wafers are grown from crystal having a regular crystal structure, with silicon having a diamond cubic structure with a lattice spacing of 5.430710 Å (0.5430710 nm).When cut into wafers, the surface is aligned in one of several relative directions known as crystal orientations. Orientation is defined by the [...]

2018-06-28 Read more...

2-25.FWHM

2-25.FWHM Full width at half maximum (FWHM) is an expression of the extent of a function, given by the difference between the two extreme values of the independent variable at which the dependent variable is equal to half of its maximum value.

2018-06-28 Read more...

2-26.TTV

Total Thickness Variation (TTV): The maximum variation in the wafer thickness. Total Thickness Variation is generally determined by measuring the wafer in 5 locations of a cross pattern (not too close to the wafer edge) and calculating the maximum measured difference in thickness. The TTV (Total Thickness Variation) value [...]

2018-06-28 Read more...

2-27.BOW

2-27.BOW Bow is the deviation of the center point of the median surface of a free, un-clamped wafer from the median surface to the reference plane. Where the reference plane is defined by three corners of equilateral triangle. This definition is based on now obsolete ASTM F534. There are a number [...]

2018-06-28 Read more...

2-28.WARP

2-28.WARP Warp is the difference between the maximum and the minimum distances of the median surface of a free, un-clamped wafer from the reference plane defined above. This definition follows ASTM F657, and ASTM F1390,which deviation from a plane of a slice or wafer centerline containing both concave and convex [...]

2018-06-28 Read more...

2-29.Resistivity

2-29.Resistivity The resistance to current flow and movement of electron and hole carries in the silicon carbide.  Resistivity is related to the ratio of voltage across the silicon to the current flowing through the silicon carbide per unit volume of silicon carbide.  The units for resistivity are  Ohm-cm, and these [...]

2018-06-28 Read more...

2-30.Dopant

2-30.Dopant A dopant, also called a doping agent, is a trace impurity element that is inserted into a substance (in very low concentrations) in order to alter the electrical properties or the opticalproperties of the substance. In the case of crystalline substances, the atoms of the dopant very commonly take [...]

2018-06-28 Read more...

2-31.N type

2-31.N type A semiconductor has electrical conductivity between that of a conductor and an insulator. Semiconductors differ from metals in their characteristic property of decreasing electrical resistivity with increasing temperature.Semiconductors can also display properties of passing current more easily in one direction than the other, and sensitivity to light. Because [...]

2018-06-28 Read more...

2-32.Semi-insulating

2-32.Semi-insulating Semi-insulating Doping with the impurities vanadium creates semi-insulating material of silicon carbide.

2018-06-28 Read more...

2-33.P type

2-33.P type A semiconductor has electrical conductivity between that of a conductor and an insulator. Semiconductors differ from metals in their characteristic property of decreasing electrical resistivity with increasing temperature.Semiconductors can also display properties of passing current more easily in one direction than the other, and sensitivity to light. Because [...]

2018-06-28 Read more...