Scheme of the <a href="https://en.wikipedia.org/wiki/High_Electron_Mobility_Transistor" class="extiw" title="en:High Electron Mobility Transistor">High Electron Mobility Transistor</a> (HEMT).
<a href="//commons.wikimedia.org/wiki/User:Sfu" title="User:Sfu">Sfu</a>
<span class="int-own-work" lang="en">Own work</span>