Si/SiGe resonant tunnelling devices separated by surrounding polysilicon

A novel design for Si/SiGe double-barrier resonant tunnelling devices is presented. The active, monocrystalline zone is embedded in polycrystalline material. The poly region consists of the same layer sequence as the active region. Both regions are deposited simultaneously by means of so-called differential molecular beam epitaxy. The I/V curve of the novel device shows a strong and a weak resonance at about 330 and 95 mV, respectively. The poly embedment can be applied as an in situ deposited separation.