Heterojunction

<p>A heterojunction is an interface between two <a href="/facts/Layer_(electronics)/x0HJl3lK">layers</a> or regions of dissimilar <a href="/facts/Semiconductor/zFf3mGTE">semiconductors</a>. These semiconducting materials have unequal <a href="/facts/Band_gap/IjIeh95l">band gaps</a> as opposed to a <a href="/facts/Homojunction/ndgHhxDK">homojunction</a>. It is often advantageous to engineer the electronic energy bands in many solid-state device applications, including semiconductor lasers, <a href="/facts/Solar_cell/3L814UCC">solar cells</a> and transistors. The combination of multiple heterojunctions together in a device is called a heterostructure, although the two terms are commonly used interchangeably. The requirement that each material be a semiconductor with unequal band gaps is somewhat loose, especially on small length scales, where electronic properties depend on spatial properties. A more modern definition of heterojunction is the interface between any two solid-state materials, including crystalline and amorphous structures of metallic, insulating, <a href="/facts/Fast_ion_conductor/oE9l9Em6">fast ion conductor</a> and semiconducting materials.
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Heterojunction open-in-new

Heterojunction