Bow and warp of semiconductor wafers and substrates are measures of the flatness of wafers.

Definitions

Bow is the deviation of the center point of the median surface of a free, un-clamped

wafer A wafer is a crisp, often sweet, very thin, flat, light and dry biscuit, often used to decorate ice cream, and also used as a garnish on some sweet dishes. Wafers can also be made into cookies with cream flavoring sandwiched between them. They ...

from the reference plane, where the reference plane is defined by . This definition is based on now obsolete

ASTM ASTM International, formerly known as American Society for Testing and Materials, is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, a ...

F534. 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.

Modifications

The above definitions were developed for

capacitance Capacitance is the capability of a material object or device to store electric charge. It is measured by the change in charge in response to a difference in electric potential, expressed as the ratio of those quantities. Commonly recognized a ...

wafer thickness gauges such as ADE 9500, and later adopted by optical gauges. Even though these standards are currently obsolete. They were withdrawn without replacement but are still widely used for characterization of semiconductor wafers, metal and glass substrates for

MEMS Microelectromechanical systems (MEMS), also written as micro-electro-mechanical systems (or microelectronic and microelectromechanical systems) and the related micromechatronics and microsystems constitute the technology of microscopic devices, ...

devices,

solar cell A solar cell, or photovoltaic cell, is an electronic device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon.Wikipedia:Footnotes on how to create references using tags which will then appear here automatically --> {{DEFAULTSORT:Bow And Warp Of Semiconductor Wafers And Substrates Semiconductor device fabrication