Abacwaningi abavela e-Moscow Institute of Physics and Technology bakwazile ukukhulisa amafilimu amancanyana e-athomu e-molybdenum disulfide afinyelela kumashumi amaningana amasentimitha isikwele. Kwaboniswa ukuthi ukwakheka kokubalulekile kungashintshwa ngokushintsha izinga lokushisa lokwenziwa. Amafilimu, abalulekile kuma-electronics kanye ne-optoelectronics, atholwe ku-900-1,000 ° Celsius. Okutholakele kushicilelwe kumagazini i-ACS Applied Nano Materials.

Izinto ezinezinhlangothi ezimbili ziheha isithakazelo esikhulu ngenxa yezakhiwo zazo ezihlukile ezivela ekwakhiweni kwazo kanye nemikhawulo yemishini ye-quantum. Umndeni wezinto ezingu-2-D uhlanganisa izinsimbi, ama-semimetals, ama-semiconductors, nama-insulators. I-graphene, okungenzeka ukuthi iyinto edume kakhulu ye-2-D, iyi-monolayer yama-athomu ekhabhoni. Inokunyakaza okuphezulu kakhulu kwenkampani yenethiwekhi okurekhodiwe kuze kube manje. Kodwa-ke, i-graphene ayinaso igebe lebhendi ngaphansi kwezimo ezijwayelekile, futhi lokho kunciphisa ukusetshenziswa kwayo.

Ngokungafani ne-graphene, ububanzi obufanele be-bandgap ku-molybdenum disulfide (MoS2) buyenza ifanelekele ukusetshenziswa kumadivayisi kagesi. Ungqimba ngalunye lwe-MoS2 lunokwakheka kwesemishi, olunongqimba lwe-molybdenum oluminyaniswe phakathi kwezingqimba ezimbili zama-athomu esibabule. Ama-heterostructures anezinhlangothi ezimbili ze-van der Waals, ahlanganisa izinto ezihlukile ze-2-D, abonisa isithembiso esihle futhi. Eqinisweni, sezivele zisetshenziswa kabanzi ekusetshenzisweni okuhlobene namandla kanye ne-catalysis. Ukuhlanganiswa kwe-Wafer-scale (indawo enkulu) ye-2-D molybdenum disulfide kukhombisa amandla enqubekelaphambili ekudalweni kwezinto zikagesi ezisobala neziguquguqukayo, ukuxhumana ngokubonakalayo kwamakhompyutha esizukulwane esilandelayo, kanye nakweminye imikhakha yezogesi kanye ne-optoelectronics.

“Indlela esiqhamuke nayo yokuhlanganisa i-MoS2 ibandakanya izinyathelo ezimbili. Okokuqala, ifilimu ye-MoO3 ikhuliswa kusetshenziswa indlela yokubeka ungqimba lwe-athomu, enikeza ukujiya kongqimba lwe-athomu olunembile futhi ivumela ukumbozwa ngokusemthethweni kwazo zonke izindawo. Futhi i-MoO3 ingatholakala kalula kuma-wafers afinyelela kumamilimitha angama-300 ububanzi. Okulandelayo, ifilimu iphathwa ngokushisa ngomhwamuko wesulfure. Ngenxa yalokho, ama-athomu omoya-mpilo ku-MoO3 athathelwa indawo ama-athomu esibabule, bese kwakheka i-MoS2. Sesivele safunda ukukhulisa amafilimu e-MoS2 azacile nge-athomu endaweni engafika amashumi amaningana amasentimitha-skwele,” kuchaza u-Andrey Markeev, inhloko ye-MIPT's Atomic Layer Deposition Lab.

Abacwaningi banqume ukuthi ukwakheka kwefilimu kuncike ekushiseni kwe-sulfurization. Amafilimu afakwe i-sulfur ku-500 ° С aqukethe izinhlamvu zekristalu, ama-nanometer ambalwa ngalinye, afakwe ku-matrix ye-amorphous. Ku-700 ° С, lawa makristalu acishe abe ngu-10-20 nm ububanzi futhi izendlalelo ze-S-Mo-S zibheke phezulu. Ngenxa yalokho, ingaphezulu linamabhondi alengayo amaningi. Isakhiwo esinjalo sibonisa umsebenzi ophezulu we-catalytic ekuphenduleni okuningi, okuhlanganisa ukusabela kokuvela kwe-hydrogen. Ukuze i-MoS2 isetshenziswe kuma-electronics, izingqimba ze-S-Mo-S kufanele zihambisane nendawo engaphezulu, okutholakala emazingeni okushisa e-sulfurization angu-900-1,000 ° С. Amafilimu avelayo mancane njengo-1.3 nm, noma izendlalelo zamangqamuzana amabili, futhi anendawo ebalulekile yezohwebo (okungukuthi, inkulu ngokwanele).

Amafilimu e-MoS2 ahlanganiswe ngaphansi kwezimo ezikahle afakwa ezakhiweni ze-metal-dielectric-semiconductor prototype, ezisekelwe ku-ferroelectric hafnium oxide futhi ziyimodeli ye-transistor esebenza ensimini. Ifilimu ye-MoS2 kulezi zakhiwo isebenze njengesiteshi se-semiconductor. I-conductivity yayo yayilawulwa ngokushintsha isiqondiso se-polarization sengqimba ye-ferroelectric. Lapho kuxhunywana ne-MoS2, impahla ye-La:(HfO2-ZrO2), eyathuthukiswa ngaphambilini elebhu ye-MIPT, yatholakala ine-polarization eyinsalela elinganiselwa ku-18 microcoulombs per square centimeter. Ngokukhuthazela okushintshwayo kwemijikelezo eyizigidi ezi-5, ifinyelele irekhodi lomhlaba langaphambili lemijikelezo eyi-100,000 yamashaneli e-silicon.