Open AccessStructural-phase junctions in the system of Pt–Si during rapid thermal treatment
Author(s) -
В. А. Пилипенко,
Ф. Ф. Комаров,
В. А. Солодуха,
В. А. Горушко
Publication year - 2020
Publication title -
doklady nacionalʹnoj akademii nauk belarusi
Language(s) - English
Resource type - Journals
eISSN - 2524-2431
pISSN - 1561-8323
DOI - 10.29235/1561-8323-2020-64-2-238-244
Subject(s) - materials science , platinum , silicide , silicon , substrate (aquarium) , sputtering , thermal treatment , atmospheric temperature range , layer (electronics) , argon , analytical chemistry (journal) , phase (matter) , sputter deposition , nanotechnology , optoelectronics , composite material , thin film , chemistry , thermodynamics , biochemistry , oceanography , physics , organic chemistry , chromatography , geology , catalysis
In recent years the interest to silicides significantly rose relating to their huge potentialities as the material of the low-Ohm contacts and interconnections of metallization of the silicon integrated circuits. In view of this the necessity appeared to consider more extensively the thermal dynamic, electric and structural peculiarities of their formation. Purpose of the work was in investigation of influence of the rapid thermal treatment on the structural –phase junctions in the system of Pt–Si during formation of platinum silicide. As samples, the Pt films were used, 43.7 nm thick and applied on the substrates of the mono-crystal silicon KEF КЭФ 0.5 with orientation (111) by means of the magnetron sputtering of the platinum target with purity of 99.95 % on the unit MRS 603 with the cryogenic pumping to the pressure not worse, than 5 · 10 –5 Pa. As the operating medium, argon was used, whose purity constituted 99.933 %. Rapid thermal treatment was performed in the nitrogen medium within the temperature range from 200 to 550 °С with a step of 50 °С and the time period of 7 s. The process of interaction of platinum with silicon during treatment of the Pt–Si system was evaluated by means of the analysis of the RBS spectra. It is demonstrated, that within the temperature range of 200 °С ≤ Т ≤ 300 °С during 7 s of the rapid thermal process on the boundary of the metal film with the substrate, formation takes place of the Pt 2 Si layer owing to diffusion of the Pt atoms into silicon via the layer of the growing silicide. The temperature Т = 300 °С is peculiar for the complete application of the Pt film during 7 s in process of the silicide formation of the single phase system of Pt 2 Si. At 350 °С ≤ Т < 450 °С formation is registered of the double phase system of Pt 2 Si → PtSi, starting from the inter-phase boundary of Si/Pt 2 Si predominantly owing to the opposite diffusion of the Si atoms into the layer of Pt 2 Si. The temperature of the rapid thermal treatment Т = 450 °С marks formation of the thermally stable balanced structure of PtSi along the entire silicide thickness, which is 50–100 °С lower and considerably more rapid, than during the long-term balanced thermal treatment.