Dry etch意思
"Dry etch" is a term used in the semiconductor manufacturing industry to describe a process that etches or removes materials from the surface of a substrate using a dry plasma rather than a wet chemical solution. This process is also known as plasma etching or reactive ion etching (RIE).
During dry etching, the substrate is placed inside a vacuum chamber where it is exposed to a plasma created from a mixture of gases. The plasma is generated by applying an electric field to the gas, which dissociates it into reactive species. These species can then react with the material on the surface of the substrate, causing it to evaporate or be sputtered off.
Dry etching is a precise process that can be used to create very small features on the surface of a semiconductor wafer. It is used in the production of integrated circuits, microelectromechanical systems (MEMS), and other devices that require precise patterning of materials.
There are several different types of dry etching processes, including:
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Reactive ion etching (RIE): A process where the substrate is exposed to a plasma of reactive gases, which react with the material on the surface of the substrate to form volatile by-products that can be easily removed.
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Inductively coupled plasma etching (ICP): A type of RIE where the plasma is generated using an inductively coupled coil. This allows for a more uniform plasma and can result in more precise etching.
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Bosch process: A type of dry etching used to create deep, narrow holes in semiconductor wafers. The process involves alternating between a Bosch etch (using a fluorocarbon plasma) and a passivation step (using a silicon-containing gas) to prevent overetching.
Dry etching is a critical step in the fabrication of semiconductor devices, as it allows for the precise removal of materials to create the desired pattern of circuits and features on the wafer.