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Deposition

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[[{{PAGENAME}}]] or Growth refers to the controlled synthesis, growth or transfer of materials as thin films on a substrate. A thin film is a layer of material ranging from fractions of a nanometer (monolayer) to several micrometers in thickness. Based on the growth dynamics which prevail during the deposition, the resulting material can be amorphous, polycrystalline, or crystalline. Deposition techniques which result in crystalline material are often referred to as epitaxial growth.
==Technologies==
| Very thin, very conformal films such as gate dieletrics, barriers, encapsulation
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{{main|Chemical vapor deposition}}
{{missing information|Parylene deposition}}
In [[chemical vapor deposition]] (CVD) , a substrate is typically heated and exposed to one or more gaseous precursors, which react and/or decompose on the substrate surface to produce the desired thin film material. CVD can be used to grow high quality, uniform thin films of various materials, such as silicon dioxide, silicon nitride, and many others. CVD can be subdivided into classifications based on pressure requirements (atmospheric (APCVD), low-pressure (LPCVD), and ultra-high vacuum (UHCVD)). It can also be classified based on the mechanism used to decompose the source gas: plasma-enhanced CVD (PECVD) breaks apart gas molecules by application of ionizing voltage; , whereas LPCVD and APCVD use elevated temperatures to cause the source gas to decompose.
<!--The LNF has fourteen [[Low pressure chemical vapor deposition| Low Pressure CVD (LPCVD)]] furnace tubes for growing doped and undoped polysilicon, silicon dioxide, and silicon nitride. and It has five [[Plasma enhanced chemical vapor deposition| Plasma Enhanced CVD (PECVD)]] chambers.-->
===Electroplating===
{{main|Electroplating}}
Electroplating (electrodeposition, electrochemical deposition) is the technique recommended when metal layers of more than a micron of thickness are needed. It is only available on conductive substrates and for conductive films. It is also the technique of choice when there is no line of sight with the surface to be deposited, for example the filling of vias in semiconductor processing. The principle is simple: positive ions are attracted to the negative electrode (anode which is the sample in the case of metal deposition) and negative ions travel towards the cathode or positive electrode. ECD is an electrochemical cell, which consists of a cathode, anode, and electrolyte that contains the ion to be deposited. Electrodeposition does not require a vacuum environment and can be done in batch processes, thus making it relatively inexpensive. It creates thick, durable film whose surface finish can be tailored depending on the requirements.
===Physical vapor deposition (PVD)===
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