InP high electron mobility transistor (HEMT) structures with In0.53Ga0.47As channels and In0.52Al0.48As barriers were grown by molecular beam epitaxy. A GaTe source was used as an n-type dopant. Conventional structures with 50-100 &ANGS; InAlAs(Te) layers and Te-delta-doped structures were investigated. Both types of structures exhibited good transport characteristics, with mobilities of 8000-10,000cm(2)/V-s and sheet densities of 1-4 x 10(12)/cm(2). Fluorination studies showed similar behavior for Si- and Te-doped HEMT structures, with donor deactivation resulting in substantial reductions in mobility and carrier density after exposure to fluorine. © 2005 Elsevier B.V. All rights reserved.