This paper proposes a model of mechanical switch with stretched nanocontacts based on an analysis of the mechanisms of electron transport within a nanocontact. We use the model proposed to derive equations describing the current in a circuit with an opening switch. The measurement data and the calculation results confirm that nanocontacts substantially modify transient states in the studied circuit and therefore their effect must be taken into account in theoretical analysis.
Słowa kluczowe: transient states in circuits, contact resistance, nanocontacts
W artykule na podstawie analizy mechanizmów transportu elektronów w obrębie nanozłączy zaproponowano model łącznika mechanicznego z rozciąganymi nanozłączami. Na podstawie modelu wyprowadzono wzory opisujące prąd płynący w obwodzie elektrycznym podczas otwierania łącznika. Wyniki pomiarów i obliczeń potwierdziły, że nanozłącza w sposób znaczny modyfikują stany nieustalone prądu w badanym obwodzie, co potwierdza konieczność uwzględnienia tego efektu w analizie teoretycznej.
Keywords: stany nieustalone w obwodach, rezystancja styku, nanozłącza
Atomic-sized conductors have been intensively studied for more than ten years, resulting in the discovery of many interesting effects that do not occur in conductors larger in size . A two-position switch  and a transistor  based on a single metal nanocontact placed on a substrate have been designed and verified to operate. Nanocontacts have been proposed to be used in sensors for the detection of lead and copper ions , terahertz signals  and linear shift . Studies have also shown that nanocontacts can form between the contacts of a mechanical relay [7, 8] or a MEMS switch . Of special importance is the observation of nanocontacts created in MEMS switches, used in radar components  and reduced power consumption systems . Intensive research is conducted to improve the reliability, lifetime and switching rate of micromechanical switches. This requires an in-depth insight into the temperature effects , adhesion , creep  and wear . The resistivity and hardness of the contact material as well as the surface topography affect the contact resistance . The observed creation of nanocontacts makes this effect relevant for the analysis of the properties of MEMS switches and circuits including MEMS switches. Using switches in an electrical circuit results in the occurrence of transient states in the circuit when a switch is being opened or closed. A switch in a circuit is modeled as a two-state device characterized by two parameters, the closed-state resistance and the open-state resistance. However, if a nanocontact forms between its terminals in the opening or closing process, a switch cannot be modeled as a two-state element. This must be taken into consideration in the analysis of transient states in an electrical circuit including such a switch, as discussed in Ref.  for the final stage of the opening process. In this paper we present measurements and a theoretical analysis of [...]
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