Demonstration of a GaN‐spacer high electron mobility transistor with low alloy scattering

A new kind of high electron mobility transistor (HEMT) based on a GaN‐spacer is reported. To confine the two‐dimensional electron gas in this AlGaN‐free HEMT, a GaN/ultrathin AlN/GaN pseudo‐hetero‐junction has been used. The effective conduction band discontinuity is given by the AlN polarization‐induced electric field. This new transistor shows a superior general performance than the standard HEMT due to a decrease in the alloy and real space transfer scattering, as well as lower ohmic contact resistance. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)