Temperature dependence of short-circuit currents in α-LiIO3 crystals

The features of short-circuit currents in polar cut samples of α-LiIO3 crystals of the hexagonal modification are investigated. Indium and silver are chosen as conductive coatings taking into account their location in the series of electrochemical tension of metals. These coating materials are typical representatives of the electrochemical series of metal tension before (indium) and after (silver) hydrogen. The measurements were carried out using the SKIP hardware and software complex in the temperature range from Troom to 210 °C without applying an external electric field. The samples under study were not preliminarily exposed to any stimulating external effects: neither temperature, nor electrical, nor radiation, etc. Graphs of short-circuit current dependences on temperature were obtained with different materials of conductive coatings and according to different measurement schemes. An optical study of the surface of conductive coatings was carried out before and after heating. The effect of the material of the conductive coatings on the magnitude and direction of short-circuit current flow in the samples was established. In the case of symmetrical conductive coatings, depending on the application of indium or silver, the currents go in different directions. In the case of asymmetrical conductive coatings, depending on the side of silver application, taking into account the polarity of the crystal, the currents have different directions of flow and a magnitude that differs by more than 2 times. The difference in the temperature dependence graphs of heating and cooling, as well as the structural change in the surface of the materials of conductive coatings, may indicate the formation of new phases.

1. Gorokhovatskii Yu.A., Bordovskii G.A. Thermally activated current spectroscopy of high-resistance semiconductors and dielectrics. Moscow: Nauka; 1991. 244 p. (In Russ.)

2. GOST 30501-97. Solid electrical insulating materials. Method of measuring electrical resistance and resistivity at elevated temperatures. Minsk: Mezhgosudarstvennyi sovet po standartizatsii, metrologii i sertifikatsii; 2001. 7 p. (In Russ.)

3. Poplavko Yu.M. Physics of dielectrics. Kiev: Vishcha shkola; 1980. 399 p. (InRuss.)

4. Rez I.S., Poplavko Yu.M. Dielectrics. Basic properties and applications in electronics. Moscow: Radio i svyaz'; 1989. 287 p. (In Russ.)

5. Blistanov A.A., Kozlova, N.S., Geras'kin V.V. The influence of surface states on the features of phase transformations and the formation of structural defects in lithium iodate crystals. Izvestiya. Non-Ferrous Metallurgy. 1996; (4): 66–71. (In Russ.)

6. Blistanov A.A., Kozlova N.S., Geras’kin V.V. The phenomenon of electrochemical self-decomposition in polar dielectrics. Ferroelectrics. 1997; 198(1): 61—66. https://doi.org/10.1080/00150199708228338

7. Iovcheva T.A. Effect of charge transfer on the degradation of a-LiIO3 crystal. Sum. of Diss. Cand. (Phys.-Math.). Moscow; 1992. 21 p. (In Russ.)

8. Blistanov A.A., Kozlova N.S., Geras'kin V.V. Phenomenon of electrochemical decomposition of polar dielectric crystals. In: Proceed. of brief descriptions of scient. discoveries – 2002. Issue 2. Diplom No. 216. Moscow: NITU "MISIS"; 2002.

9. Buzanov O.A., Zabelina E.V., Kozlova N.S., Sagalova T.B. Near-electrode processes in lanthanum-gallium tantalate crystals. Crystallography Reports. 2008; 53(5): 853–857.

10. Kozlova N.S., Zabelina E.V., Bykova M.B., Kozlova A.P. Features of manifestation of surface electrochemical processes in ferroelectric crystals with low-temperature phase transitions. Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering. 2018; 21(3): 146—155. (In Russ.). https://doi.org/10.17073/1609-3577-2018-3-146-155

11. Blistanov A.A. Crystals of quantum and nonlinear optics. Moscow: MISIS; 2000. 432 p. (In Russ.)

12. Portnov O.G. Technology of bulk single crystals of semiconductors and dielectrics. Growing technological single crystals of lithium iodate for nonlinear optics devices. Moscow: Izd. Dom NITU "MISIS"; 2015. 142 p. (In Russ.)

13. Bogdanov S.V. (ed.). Avdienko K.I., Bogdanov S.V., Arkhipov S.M.; Kidyarov B.I. Lithium iodate: Growing crystals, their properties and applications. Novosibirsk: Nauka: Sib. otd-nie;1980. 144 p. (In Russ.)

14. De Boer J.L., Van Bolhuis F., Olthof-Hazekamp R.V. Re-investigation of the crystal structure of lithium iodate. Acta Crystallographica. 1966; 21(5): 841—843. https://doi.org/10.1107/S0365110X66004031

15. Shaskol'skaya M.P. (ed.). Blistanov A.A., Bondarenko V.S., Perelomova N.V. Acoustic crystals. Moscow: Nauka; 1982. 356 p. (In Russ.)

16. Perelomova N.V., Tagieva M.M. Crystal physics. Moscow: Izd. Dom NITU "MISIS"; 2013. 408 p. (In Russ.)

17. Pirozerski A.L., Charnaya E.V., Lebedeva E.L., Filippov K.V., Zalesski V.G. Dielectric studies of A α-LiIO3 crystals grown from neutral and alkaline solutions. Physics of the Solid State. 2009; 51(4): 708—713.

18. Korol'kov D.V. Fundamentals of inorganic chemistry. Moscow: Prosveshchenie; 1982. 271 p. (In Russ.)

19. Shportenko A.S., Kubasov I.V., Kislyuk A.M., Turutin A.V., Malinkovich M.D., Parkhomenko Yu.N. The effect of contact phenomena on the measurement of electrical conductivity of reduced lithium niobate. Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering. 2021; 24(3): 199—210. (In Russ.). https://doi.org/10.17073/1609-3577-2021-3-199-210

20. Jen S., Bobkowski R. Black lithium niobate SAW device fabrication and performance evaluation. In: Proc. IEEE ultrasonics symposium. October 22–25, 2000 San Juan, PR, USA; 2000. P. 269—273. https://doi.org/10.1109/ultsym.2000.922554

21. Palatnikov M.N., Sandler V.A., Sidorov N.V., Makarova O.V., Manukovskaya D.V. Conditions of application of LiNbO3 based piezoelectric resonators at high temperatures. Physics Letters A. 2020; 384(14): 126289. https://doi.org/10.1016/j. physleta.2020.126289

22. Singh K. Electrical conductivity of non-stoichiometric LiNbO3 single crystals. Ferroelectrics. 2004; 306(1): 79—92. https://doi.org/10.1080/00150190490457348

23. Yatsenko A.V., Pritulenko A.S., Yevdokimov S.V., Sugak D.Y., Syvorotka I.I., Suhak Y.D., Solskii I.M., Vakiv M.M. The influence of annealing in saturated water vapor on LiNbO3 crystals optical and electrical properties. Solid State Phenomena. 2015; 230: 233—237. https://doi. org/10.4028/www.scientific.net/SSP.230.233

24. Akhmadullin I.Sh., Golenishchev-Kutuzov V.A., Migachev S.A., Mironov S.P. Low-temperature electrical conductivity of congruent lithium niobate crystals. Physics of the Solid State. 1998; 40(7): 1190—1192.

25. Schröder M., Haußmann A., Thiessen A., Soergel E., Woike T., Eng L.M. Conducting domain walls in lithium niobate single crystals. Advanced Functional Materials. 2012; 22(18): 3936—3944. https://doi.org/10.1002/adfm.201201174

26. Yatsenko A.V., Yevdokimov S.V., Pritulenko A.S., Sugak D.Y., Solskii I.M. Electrical properties of LiNbO3 crystals reduced in a hydrogen atmosphere. Physics of the Solid State. 2012; 54(11): 2231—2235. https://doi.org/10.1134/S1063783412110339

27. Esin A.A., Akhmatkhanov A.R., Shur V.Y. The electronic conductivity in single crystals of lithium niobate and lithium tantalate family. Ferroelectrics. 2016; 496(1): 102—109. https://doi.org/10.1080/00150193.2016.1157438

28.