Masu bincike daga Cibiyar Kimiyya da Fasaha ta Moscow sun yi nasarar haɓaka fina-finan siraran ƙwayoyin cuta na molybdenum disulfide wanda ya kai dubun santimita da dama. An nuna cewa za'a iya gyaggyara tsarin kayan ta hanyar canza yanayin yanayin haɗin. Fina-finan, masu mahimmanci ga kayan lantarki da na'urorin lantarki, an samo su a 900-1,000 ° Celsius. An buga sakamakon binciken a cikin mujallar ACS Applied Nano Materials.

Abubuwa masu girma biyu suna jawo sha'awa sosai saboda keɓaɓɓen kaddarorinsu waɗanda ke fitowa daga tsarinsu da ƙayyadaddun injin ƙididdigewa. Iyalin kayan 2-D sun haɗa da ƙarfe, semimetal, semiconductor, da insulators. Graphene, wanda watakila shine mafi shaharar kayan 2-D, shine monolayer na carbon atom. Yana da mafi girman motsi-dangi da aka rubuta zuwa yau. Koyaya, graphene ba shi da tazarar band a ƙarƙashin daidaitattun yanayi, kuma hakan yana iyakance aikace-aikacen sa.

Ba kamar graphene ba, mafi kyawun faɗin bandgap a cikin molybdenum disulfide (MoS2) ya sa ya dace don amfani a cikin na'urorin lantarki. Kowane Layer MoS2 yana da tsarin sanwici, tare da Layer na molybdenum wanda aka matse tsakanin layuka biyu na atom na sulfur. Hanyoyi biyu na van der Waals heterostructures, waɗanda ke haɗa nau'ikan 2-D daban-daban, suna nuna babban alkawari kuma. A gaskiya ma, an riga an yi amfani da su sosai a aikace-aikace masu alaka da makamashi da catalysis. Wafer-sikelin (babban yanki) kira na 2-D molybdenum disulfide yana nuna yuwuwar ci gaban ci gaba a cikin ƙirƙirar na'urorin lantarki masu sauƙi da sassauƙa, sadarwa ta gani don kwamfutoci na gaba, da kuma a wasu fannonin lantarki da optoelectronics.

“Hanyar da muka fito da ita don haɗa MoS2 ta ƙunshi matakai biyu. Na farko, fim ɗin MoO3 yana girma ta amfani da dabarar ƙaddamar da ƙirar atomic Layer, wanda ke ba da ƙaƙƙarfan kauri na atomic kuma yana ba da izinin rufe duk saman. Kuma ana iya samun MoO3 cikin sauƙi akan wafers har zuwa milimita 300 a diamita. Na gaba, fim ɗin yana da zafi-biyar a cikin sulfur tururi. A sakamakon haka, ana maye gurbin kwayoyin oxygen a cikin MoO3 da kwayoyin sulfur, kuma an kafa MoS2. Mun riga mun koyi girma fina-finan MoS2 na atomically a kan wani yanki da ya kai dubunnan santimita murabba'i," in ji Andrey Markeev, shugaban Cibiyar Atomic Layer Deposition Lab na MIPT.

Masu binciken sun ƙaddara cewa tsarin fim ɗin ya dogara da zafin jiki na sulfurization. Fina-finan sulfurized a 500°C sun ƙunshi hatsin lu'ulu'u, 'yan nanometers kowannensu, wanda aka saka a cikin matrix amorphous. A 700 ° C, waɗannan crystallites suna da kusan 10-20 nm a fadin kuma S-Mo-S yadudduka suna daidaitawa zuwa saman. A sakamakon haka, saman yana da nau'i-nau'i masu yawa. Irin wannan tsarin yana nuna babban aiki mai ƙarfi a cikin halayen da yawa, gami da halayen haɓakar hydrogen. Don MoS2 da za a yi amfani da shi a cikin kayan lantarki, S-Mo-S ya kamata ya kasance daidai da saman, wanda aka samu a yanayin zafi na 900-1,000 ° C. Fina-finan da aka samu sun kai sirara kamar 1.3 nm, ko kuma nau'ikan kwayoyin halitta guda biyu, kuma suna da wani yanki mai mahimmanci na kasuwanci (watau babban isa).

Fina-finan MoS2 da aka haɗa a ƙarƙashin ingantattun yanayi an gabatar da su cikin ƙirar ƙarfe-dielectric-semiconductor samfur, waɗanda suka dogara akan ferroelectric hafnium oxide da ƙirar transistor mai tasirin filin. Fim ɗin MoS2 a cikin waɗannan sifofin yayi aiki azaman tashar semiconductor. An sarrafa tafiyar da aikin sa ta hanyar canza hanyar polarization na Layer ferroelectric. Lokacin da ake hulɗa da MoS2, kayan La: (HfO2-ZrO2), wanda aka haɓaka a baya a cikin dakin gwaje-gwaje na MIPT, an gano yana da ragowar polarization na kusan 18 microcoulombs a kowace santimita murabba'i. Tare da juriyar juriya na miliyon 5 na hawan keke, ya zama rikodin rikodin duniya na baya na 100,000 don tashoshin silicon.