silicon technical terms-2
Dimple-A concave depression found on the surface of a wafer that is visible to the eye under the correct lighting conditions.
Donor - A contaminate that has donated extra “free” electrons, thus making a wafer “N-Type”.
Dopant -An element that contributes an electron or a hole to the conduction process, thus altering the conductivity.
Dopants for silicon wafers are found in Groups III and V of the Periodic Table of the Elements.
Doping - The process of the donation of an electron or hole to the conduction process by a dopant.
Edge Chip and Indent - An edge imperfection that is greater than 0.25 mm.
Edge Exclusion Area -The area located between the fixed quality area and the periphery of a wafer.
Edge Exclusion, Nominal (EE) -The distance between the fixed quality area and the periphery of a wafer.
Edge Profile -The edges of two bonded wafers that have been shaped either chemically or mechanically.
Etch - A process of chemical reactions or physical removal to rid the wafer of excess materials.
Fixed Quality Area (FQA) - The area that is most central on a wafer surface.
Flat - A section of the perimeter of a wafer that has been removed for wafer orientation purposes.
Flat Diameter -The measurement from the center of the flat through the center of the wafer to the opposite edge of the wafer.
Four-Point Probe - Test equipment used to test resistivity of wafers.
Furnace and Thermal Processes -Equipment with a temperature gauge used for processing wafers. A constant temperature is required for the process.
Front Side - The top side of a silicon wafer. (This term is not preferred; use front surface instead.)
Goniometer - An instrument used in measuring angles.
Gradient, Resistivity (not preferred; see resistivity variation)
Groove - A scratch that was not completely polished out.
Hand Scribe Mark -A marking that is hand scratched onto the back surface of a wafer for identification purposes.
Haze - A mass concentration of surface imperfections, often giving a hazy appearance to the wafer.
Hole - Similar to a positive charge, this is caused by the absence of a valence electron.
Ingot - A cylindrical solid made of polycrystalline or single crystal silicon from which wafers are cut.
Laser Light-Scattering Event - A signal pulse that locates surface imperfections on a wafer.
Lay - The main direction of surface texture on a wafer.
Light Point Defect (LPD) (Not preferred; see localized light-scatterer)
Lithography - The process used to transfer patterns onto wafers.
Localized Light-Scatterer -One feature on the surface of a wafer, such as a pit or a scratch that scatters light. It is also called a light point defect.
Lot - Wafers of similar sizes and characteristics placed together in a shipment.


