What is a polished wafer?
Polished wafers are silicon wafers with one or both sides polished to a mirror surface. Our polished wafers are superior in properties such as flatness and cleanliness. They have earned an excellent reputation for high quality and precision that meets the needs of the ULSI age.
What is epitaxial silicon wafer?
A silicon epitaxial wafer is a single-crystalline silicon wafer. It is made up of many atoms, which can be heteroepitaxy or homoepitaxy. For example, a noncrystalline film can be formed on top of a crystalline layer. These layers are the same atoms that make up the silicon layers.
What is epitaxial layer?
Epitaxy refers to a type of crystal growth or material deposition in which new crystalline layers are formed with one or more well-defined orientations with respect to the crystalline seed layer. The deposited crystalline film is called an epitaxial film or epitaxial layer.
Why is epitaxial layer needed?
In a word, the epitaxial layer is easier to obtain a perfect and controllable crystal structure than the substrate, which is more conducive to the application and development of the material.
What kind of wafers are there?
Types of semiconductor wafers:
Why are silicon wafers polished?
The need for polishing silicon wafer is to obtain a smooth surface for sprucing the semiconductor devices on the wafer surface. In CMP the chemical action weakens the atomic bonding of the wafer surface and the rotatory mechanical action assist the material removal.
What is EPI in wafer?
An epitaxial wafer (also called epi wafer, epi-wafer, or epiwafer) is a wafer of semiconducting material made by epitaxial growth (epitaxy) for use in photonics, microelectronics, spintronics, or photovoltaics.
What is epitaxy semiconductor?
epitaxy, the process of growing a crystal of a particular orientation on top of another crystal, where the orientation is determined by the underlying crystal. The creation of various layers in semiconductor wafers, such as those used in integrated circuits, is a typical application for the process.
What is epitaxial grain growth?
Epitaxial alignment has been obtained by means of grain growth in polycrystalline films deposited on single-crystal substrates. A theory for epitaxial grain growth is outlined and results given for experiments on Au, AI, Cu, and Ag films on vacuum-cleaved NaCI, KBr, KCI, or mica.
What is epitaxial silicon transistor?
epitaxial transistor in British English (ˌɛpɪˈtæksɪəl ) a transistor made by depositing a thin pure layer of semiconductor material (epitaxial layer) onto a crystalline support by epitaxy. The layer acts as one of the electrode regions, usually the collector. Collins English Dictionary.
How is epitaxial growth achieved?
4.5 Epitaxial Growth Epitaxial growth is broadly defined as the condensation of gas precursors to form a film on a substrate. Liquid precursors are also used, although the vapor phase from molecular beams is more in use. Vapor precursors are obtained by CVD and laser ablation.
How are wafers used?
In electronics, a wafer (also called a slice or substrate) is a thin slice of semiconductor, such as a crystalline silicon (c-Si), used for the fabrication of integrated circuits and, in photovoltaics, to manufacture solar cells. The wafer serves as the substrate for microelectronic devices built in and upon the wafer.