Zalyalov Timur Maratovich
@isp.nsc.ru
Rzhanov Institute of Semiconductor Physics Siberian Branch of Russian Academy of Sciences
RESEARCH, TEACHING, or OTHER INTERESTS
Condensed Matter Physics
5
Scopus Publications
Scopus Publications
- Adhesion layer free room-temperature pulsed laser deposition of ultrathin Au films
Danil A. Kolosovsky, Timur M. Zalyalov, Sergei A. Ponomarev, Nikolay B. Miskiv, Alexey A. Morozov, Yuri G. Shukhov, Alexander V. Shevlyagin, Aleksandr A. Kuchmizhak, and Sergey V. Starinskiy
Elsevier BV - Infrared photoresponse of GeSiSn p-i-n photodiodes based on quantum dots, quantum wells, pseudomorphic and relaxed layers
V A Timofeev, I V Skvortsov, V I Mashanov, A A Bloshkin, I D Loshkarev, V V Kirienko, T M Zalyalov, and K A Lozovoy
IOP Publishing
Abstract Structural and photoelectric properties of p–i–n photodiodes based on GeSiSn/Si multiple quantum dots (QDs) both on Si and silicon-on-insulator substrates were investigated. Elastic strained state of grown films was demonstrated by x-ray diffractometry. Annealing of p–i–n structures before the mesa fabrication can improve the ideality factor of current–voltage characteristics. The lowest dark current density of p–i–n photodiodes based on QDs at the reverse bias of 1 V reaches the value of 0.8 mA cm−2. The cutoff wavelength shifts to the long-wavelength region with the Sn content increase. Maximum cutoff wavelength value is found to be 2.6 μm. Moreover, multilayer periodic structures with GeSiSn/Ge quantum wells and GeSiSn relaxed layers on Ge substrates were obtained. Reciprocal space maps were used to study the strained state of GeSiSn layers. The optimal growth parameters were determined to obtain slightly relaxed GeSiSn layers. Designed p–i–n photodiodes based on these structures demonstrated the minimal dark current density of 0.7 mA cm−2 and the cutoff wavelength of about 2 μm. - Electron and hole bipolar injection in magnesium oxide films
Timofey V. Perevalov, Damir R. Islamov, Timur M. Zalyalov, Andrei A. Gismatulin, Vladimir A. Golyashov, Oleg E. Tereshchenko, Dmitry V. Gorshkov, and Vladimir A. Gritsenko
AIP Publishing
It is assumed that the reliability and functionality of nonvolatile memory elements based on MgO are determined by the charge transport in MgO. In the present study, the type of MgO conductivity is established using experiments on the injection of minority charge-carriers in the n(p)-Si/MgO/Mg structures. It is shown that electrons and holes contribute to the MgO conductivity, causing bipolar charge transport. Using ab initio simulations, it was found that native point defects in MgO can provide both electron and hole conductivity. - The Influence of the Dopant Concentration on the Ferroelectric Properties and theTrap Density in Hf<inf>0.5</inf>Zr<inf>0.5</inf>O<inf>2</inf>:La Films During Endurance Cycling
Timur M. Zalyalov and Damir R. Islamov
IEEE
The ferroelectric properties evolution of Hf0.5Zr0.5O2:La films in metal-ferroelectric-metal structures with different dopant content of 0, 2, and 3. 5 mol.% is studied. Hafnium oxide-based materials are being actively studied for their application in electronic non-volatile memory devices. It is shown that an increase in the La content leads to a significant wake-up effect and a decrease in the residual polarization maximum. At the same time, the number of endurance cycles before the structure breakdown increases by orders of magnitude. The switching voltage amplitude was selected to achieve the optimal memory window with the greatest number of endurance cycles. The residual polarization and the trap density dependencies during cyclic switching are obtained. It is shown that the trap density remains unchanged up to 10$^{\\mathbf{4\\, }}$ switching cycles and increases rapidly before breakdown in structures with different La content. Conclusions are drawn about the correlation of the residual polarization magnitude and the trap density in ferroelectric Hf0.5Zr0.5O2:La films. - Impact of oxygen vacancy on the ferroelectric properties of lanthanum-doped hafnium oxide
Damir R. Islamov, Timur M. Zalyalov, Oleg M. Orlov, Vladimir A. Gritsenko, and Gennady Ya. Krasnikov
AIP Publishing
The discovery of ferroelectric properties in hafnium oxide has brought back the interest in the ferroelectric non-volatile memory as a possible alternative for low power consumption electronic memories. As far as real hafnium oxide-based materials have defects like oxygen vacancies, their presence might affect the ferroelectric properties due to oxygen atom movements during repolarization processes. In this work, the transport experiments are combined with the modeling to study evolution of the oxygen vacancy concentration during the endurance and to determine the optimal defect density for a higher residual polarization in lanthanum-doped hafnium oxide.