Kaya I.I.Dellow, M.W.Bending, S.J.Linfield, E.H.Rose P.D.Ritchie, D.A.Jones G.A.C.2016-02-082016-02-0819960268-1242http://hdl.handle.net/11693/25850Recent advances using in situ focused ion beam implantation during an MBE growth interruption have been exploited to fabricate planar GaAs hot electron structures without the need for shallow ohmic contacts. This novel fabrication route shows a very high yield and has been used to demonstrate a prototype high-frequency oscillator structure based on electron multiplication in the base layer. Existing devices show transfer factors in excess of unity as well as reversal of the base current at high injection levels, which are the prerequisites for oscillator action. Future improvements in device design are discussed.EnglishElectric currentsFabricationHot carriersIn situ processingIon beamsMolecular beam epitaxyOhmic contactsOscillators (electronic)Semiconducting gallium arsenideSemiconductor device structuresTransistorsHot electron structureHot electron transistor oscillatorIon beam implantationIon implantationArticle