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Current instability phenomena in a tunnel diode and electron self-organization processes In the article the mechanisms of electric instability in semiconductors are considered. The origin of negative differential conductivity of different types are described. On the example of functioning of the tunnel diode the mechanism of formation of the concentrated instability in semiconductors resulting in N-shaped voltampere characteristic of the diode is considered. It is shown that the «semiconductor structure consisting of two layers of semiconductors with different type of conductivity and an external source of electric energy» system can be considered as an open non-equilibrium thermodynamic system in which self-organization processes are possible. Operation of the tunnel diode in terms of the theory of self-organization in semiconductor structures is analysed. Processes of self-organization are resulted by change of concentration of carriers of a charge in power zones of p-and n-semiconductors of types which make the tunnel diode and therefore the direction of streams of electrons changes. The description of the movement of carriers of a charge in the considered semiconductor structure at various values and external shift is given: in an equilibrium state, at the return shift; at the direct shift and tension which have values less peak value; and tension exceeding «voltage dip». In a thermodynamic non-equilibrium system there can be processes of self-organization of various nature-tunneling and injection of electrons. At the same time the direction of processes of self-organization is defined by features of power ranges of the semiconductors making the tunnel diode and intensity of interaction between system elements.

Physical processes in Gunn diode and energy balance In article the physical processes happening in Gunn diode which is under the influence of strength electric field exceeding threshold value are analyzed. It is shown that because of transition of electrons from the lower central power area to the top side valley of a power range of arsenide of gallium carriers of a charge are divided into two groups: the «light» and «heavy» electrons having respectively big and smaller drift mobility. At the same time there is an electric domain which resistance is more than resistance of other part of Gunn diode of therefore tension of internal electric field of the diode will exceed electric field strength out of the domain. With growth of tension of external electric field falling of potential on the domain grows, and out of the domain decreases. Growth of drift speed of electrons of the electric domain and reduction of drift speed of electrons out of it is at the same time observed. Formation of the domain comes to the end when drift velocity electrons in the domain and out of it are compared. Steady state in Gunn diode is established when integral Lagrangian reaches the minimum value.

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