D.S. Loginov – Post-graduate Student, 

Department «Micro- and nanoelectronics», Ryazan State Radio Engineering University named after V.F. Utkin E-mail: skooobel@gmail.com

V.G. Litvinov – Ph.D.(Phys.-Math.), Associate Professor, Leading Research Scientist, 

Department «Micro- and nanoelectronics», Ryazan State Radio Engineering University named after V.F. Utkin E-mail: vglit@yandex.ru

T.A. Kholomina – Dr.Sc.(Phys.-Math.), Professor, Head of Department «Micro- and nanoelectronics»,  Ryazan State Radio Engineering University named after V.F. Utkin

E-mail: marta.tap@yandex.ru

A.R. Semenov – Post-graduate Student, 

Department «Micro- and nanoelectronics», Ryazan State Radio Engineering University named after V.F. Utkin E-mail: sem-a-sem@mail.ru

N.B. Rybin – Ph.D.(Phys.-Math.), Associate Professor, 

Department «Micro- and nanoelectronics», Ryazan State Radio Engineering University named after V.F. Utkin E-mail: nikolay.rybin@yandex.ru

The problem of monitoring the parameters of sealed magnetically controlled contacts or reed switches is considered. A technique for monitoring the noise characteristics of reed switches to analyze their degradation is proposed. The results of low-frequency noise spectral power density (PSD) characteristics and parameters of sealed magnetically-controlled contacts subjected to accelerated tests study are presented. The methods used are low-frequency noise spectroscopy and scanning electron microscopy. A device has been developed that allows to set the parameters of accelerated reed switch tests that are the number of switching, current, voltage and electric active power. Two lots of 10 reed switches MKA-14103 were used as experimental samples. The first set consisted of reed switches with Au – Ru and Fe contact coatings, the second set contained reed switches without contact coatings (50% Fe and 50% Ni alloy). Reed switches underwent multiple from 2,000 to 10,000 switching cycles. Reed switches with a different commutation number were first investigated by low-frequency noise spectroscopy in the frequency range from 10−2 to 103 Hz. After root tests the reed switches were destroyed and the contact surface was investigated using a JEOL 6610 LV scanning electron microscope. The spectra of low-frequency noise were measured using an automated complex using a preamplifier adapted to study low-impedance samples with a gain in the range of 10−1000. At the same time, a direct current of 0.1−100 mA was passed through the reed switch. A study of the contact spots size dependence on the magnitude of the transmitted forward current and the number of switching magnetically controlled contacts using scanning electron microscopy was made. After root tests protrusions appeared on the contact surface having a rounded shape on the anode with an aperture inside and an annular shape on the cathode. The nature of the protrusions is associated with the processes of local melting and the contact parts material electromigration. A relationship between the PSD level of low-frequency noise and the type of contact coating and the number of switching operations was found. It is shown that the method of spectroscopy of low-frequency noise can be used for diagnostics and study the reed switches reliability and degradation.

1. Karabanov S.M., Maizels R.M., Shoffa V.N. Magnitoupravlyaemye kontakty (gerkony) i izdeliya na ikh osnove. Pod red. V.N. Shoffy. Dolgoprudnyi: Izdatelskii Dom «Intellekt». 2011. 408 s. (in Russian)
2. Zhigalskii G.P. Neravnovesnyi 1/f-shum v provodyashchikh plenkakh i kontaktakh. UFN. 2003. T. 173. № 5. S. 465−490. (in Russian)
3. Zhigalskii G.P. Shumy vida 1/f i nelineinye effekty v tonkikh metallicheskikh plenkakh. UFN. 1997. T. 167. № 6. S. 623−647. (in Russian)
4. Kholomina T.A., Kostryukov S.A., Litvinov V.G., Ermachikhin A.V. Spektroskopiya nizkochastotnykh shumov poluprovodnikovykh priborov. Datchiki i sistemy. 2013. № 5. S. 15−20. (in Russian)
5. Semenov A.R., Litvinov V.G., Kholomina T.A., Ermachikhin A.V., Kostryukov S.A., Loginov D.S. Razrabotka avtomatizirovannogo kompleksa dlya issledovaniya spektrov nizkochastotnogo shuma v elementakh i strukturakh elektronnoi tekhniki. Radiotekhnika. 2017. № 5. S. 179−185. (in Russian)
6. Kulikov E.I. Metody izmereniya sluchainykh protsessov. M.: Radio i svyaz. 1986. 272 s. (in Russian)
7. Kholomina T.A., Kostryukov S.A., Laktyushkin A.S. Issledovanie poluprovodnikovykh barernykh struktur metodom spektroskopii nizko– chastotnogo shuma. Vestnik Ryazanskogo gosudarstvennogo radiotekhnicheskogo universiteta. 2012. № 39. Ch. 1. S. 74−78. (in Russian)
8. Vishnyakov N.V., Vorobev Yu.V., Gudzev V.V., Ermachikhin A.V., Kusakin D.S., Litvinov V.G., Maslov A.D., Mishustin V.G., Tolkach N.M., Kholomina T.A.Razvitie metodov issledovaniya poluprovodnikovykh materialov i pribornykh struktur mikro- i nanoelektroniki. Vestnik Ryazanskogo gosudarstvennogo radiotekhnicheskogo universiteta. 2017. № 60. S. 164−170. (in Russian)