The production of ohmic contacts to heterobipolar nanostructures has a number of peculiarities. In addition to the basic requirement of minimizing the contact resistance, the contacts to this type of structures have a transient layer, the penetration depth of which should not exceed the emitter layer thickness, otherwise the short-circuit of the emitter-base p - n -junction is possible. We have examined the influence of the main technological parameters of annealing on contact characteristics. As a result, optimization of the low-resistance ohmic contact to heterobipolar transistor layers obtaining process has been carried out. The ohmic contacts to the n -layers of heterobipolar nanoheterostructures based on gallium arsenide, obtained by the layer-by-layer electron-beam deposition of Ge/Au/Ni/Au, have been investigated. The diffusion profiles of the Ge impurity doping distribution as a function of time and the temperature of RTA have been calculated and SEM investigated. It has been determined that RTA for 60 sec at temperature of 398 °C makes it possible to obtain the ohmic contacts with low resistance, smooth morphology of the surface and the minimum size of the transition layer.
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