What does epitaxial transistor mean?

/ (ˌɛpɪˈtæksɪəl) / noun. 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.

What is a epitaxial transistor used for?

The direct descendants of the epitaxial transistor exist in nearly every advanced electronic device imaginable: flat screens, digital camera CCDs, cell phones, integrated circuits, computer processors, memory chips, solar cells, and a myriad of other devices that form the foundations of all modern technological systems …

What is meant by epitaxy?

The term epitaxy comes from the Greek roots epi, meaning “above”, and taxis, meaning “in ordered manner”. It can be translated “to arrange upon”. Epitaxy refers to the deposition of an overlayer on a crystalline substrate, where the overlayer is in registry with the substrate.

What is planar transistor?

[′plā·nər tran′zis·tər] (electronics) A transistor constructed by an etching and diffusion technique in which the junction is never exposed during processing, and the junctions reach the surface in one plane; characterized by very low leakage current and relatively high gain.

Which is the best description of an epitaxial transistor?

epitaxial transistor. (ˌɛpɪˈtæksɪəl) n. (Electronics) a transistor made by depositing a thin pure layer of semiconductor material (epitaxial layer) onto a crystalline support by epitaxy.

How is the n type channel formed in an epitaxial device?

The n-type channel is formed by the n-type epitaxial layer region between the p + diffused layer (gate) and the p-type substrate. The processing sequence for the device follows closely to that of the double-diffused transistor and is summarized below.

What is the sheet resistance of an epitaxial device?

Sheet resistance is of about 200 ohm per square. The drive-in diffusion is performed in an oxidizing ambient so that oxide is regrown in the windows that were produced in the preceding step. Using second photolithography, oxide windows are etched for the emitter diffusion.

What are the characteristics of an epitaxial diode?

Referring to figure (b) given above, the fabrication steps for the epitaxial planar diode are as follows. The starting material is n/n + epitaxial wafer with a 0.005-ohm-cm (Sb-doped} substrate and an epitaxial layer of anywhere from 5 to 25 micro meters thick and phosphorus doped to resistivities in the range 5 to 50-ohm-cm.