Asymmetric Spacer Layer Tunnel In0.18Ga0.82As/AlAs (ASPAT) Diode using double quantum wells for dual functions: Detection and oscillation

The work reported here proposes a new Asymmetric Spacer Layer Tunnel (ASPAT) Diode structure. The most interesting feature found from this study is the dual functions capability of the proposed device. In order to expand the device functionality, the new ASPAT has been designed with a thin potential barrier of AlAs sandwiched between double quantum wells of In18Ga.82As. The work focuses on experimental and physical modelling of this novel In0.18Ga0.82As/AlAs double quantum well ASPAT diode on GaAs. To broaden and extend the operating frequency range, three different mesa size devices (100×100 μm2, 30×30 μm2 and 6×6 μm2) were fabricated and measured. The I-V characteristics of these devices show negative deferential resistance (NDR) region as well as zero bias turn-on feature which give this device capability to work as both a detector and oscillator depending upon bias.