Abaphandi abavela kwiZiko laseMoscow leFiziksi neTekhnoloji bakwazile ukukhulisa iifilim ezibhityileyo ze-atomically ze-molybdenum disulfide ezithatha ukuya kuthi ga kwishumi leesentimitha zesikwere. Kwaboniswa ukuba isakhiwo sezinto eziphathekayo sinokuguqulwa ngokutshintsha ubushushu be-synthesis. Iifilimu, ezibalulekileyo kwi-electronics kunye ne-optoelectronics, zifunyenwe kwi-900-1,000 ° Celsius. Iziphumo zapapashwa kwiphephancwadi ACS Applied Nano Materials.

Iimathiriyeli ezinomacala amabini zitsala umdla omkhulu ngenxa yeepropathi zazo ezizodwa ezivela kubume bazo kunye nezithintelo zomatshini wobungakanani. Intsapho yezixhobo ze-2-D ibandakanya isinyithi, i-semimetals, i-semiconductors, kunye ne-insulators. IGraphene, mhlawumbi eyona nto idumileyo ye-2-D, yimonolayer yeeathom zekhabhoni. Ineyona ntlawulo iphezulu yokushukumiseka erekhodiweyo ukuza kuthi ga ngoku. Nangona kunjalo, igraphene ayinayo i-gap yebhendi phantsi kweemeko eziqhelekileyo, kwaye oko kunciphisa usetyenziso lwayo.

Ngokungafaniyo negraphene, ububanzi obufanelekileyo be-bandgap kwi-molybdenum disulfide (MoS2) yenza ukuba ilungele ukusetyenziswa kwizixhobo zombane. Umaleko ngamnye we-MoS2 unesakhiwo sesandwich, kunye nomaleko we-molybdenum ecudiweyo phakathi kweeleya ezimbini zeeathom zesulfure. I-Two-dimensional van der Waals heterostructures, edibanisa izinto ezahlukeneyo ze-2-D, ibonisa isithembiso esikhulu ngokunjalo. Enyanisweni, sele zisetyenziswe ngokubanzi kwizicelo ezinxulumene namandla kunye ne-catalysis. I-Wafer-scale (indawo enkulu) i-synthesis ye-2-D molybdenum disulfide ibonisa amandla okuqhubela phambili kwinkqubela phambili ekudalweni kwezixhobo zombane ezicacileyo kunye neziguquguqukayo, unxibelelwano lwamehlo kwiikhompyutheni zesizukulwana esilandelayo, kunye nakweminye imimandla yombane kunye ne-optoelectronics.

“Indlela esize nayo yokwenza i-MoS2 ibandakanya amanyathelo amabini. Okokuqala, ifilim ye-MoO3 ikhuliswa kusetyenziswa indlela yokubeka umaleko weathom, ebonelela ngobungqingqwa bomaleko weathom obuchanekileyo kwaye ivumela ukugquma ngokusesikweni kuyo yonke imiphezulu. Kwaye i-MoO3 inokufumaneka ngokulula kwii-wafers ezifikelela kwi-300 millimeters ububanzi. Emva koko, ifilimu iphathwa ngobushushu kumoya wesulfure. Ngenxa yoko, iiathom ze-oksijini kwi-MoO3 zitshintshwa zii-athomu zesulfure, kwaye i-MoS2 yenziwe. Sele sifundile ukukhulisa iifilim ze-atom ze-MoS2 ezibhityileyo kwindawo ukuya kuthi ga kwishumi leesentimitha zesikwere,” ucacise watsho u-Andrey Markeev, intloko ye-MIPT's Atomic Layer Deposition Lab.

Abaphandi banqume ukuba isakhiwo sefilimu sixhomekeke kwiqondo lokushisa le-sulfurization. Iifilimu ezifakwe kwi-sulfur kwi-500 ° С ziqulethe i-crystalline grains, i-nanometers embalwa nganye, ifakwe kwi-matrix ye-amorphous. Kwi-700 ° С, ezi crystallites zi malunga ne-10-20 nm ngaphesheya kwaye iileyile ze-S-Mo-S zijoliswe kwi-perpendicular kumphezulu. Ngenxa yoko, umphezulu unamabhondi amaninzi ajingayo. Ulwakhiwo olunjalo lubonisa umsebenzi ophezulu we-catalytic kwiimpendulo ezininzi, kubandakanya impendulo ye-hydrogen. Ukuze i-MoS2 isetyenziswe kwi-electronics, iileyile ze-S-Mo-S kufuneka zihambelane nomphezulu, ophunyezwa kwiqondo lokushisa le-sulfurization ye-900-1,000 ° С. Iifilimu ezibangelwayo zincinci njenge-1.3 nm, okanye i-molecular layers ezimbini, kwaye zinendawo yorhwebo ebalulekileyo (okt, inkulu ngokwaneleyo).

Iifilimu ze-MoS2 ezidityanisiweyo phantsi kweemeko ezifanelekileyo zaziswa kwi-metal-dielectric-semiconductor prototype structures, ezisekelwe kwi-ferroelectric hafnium oxide kunye nemodeli ye-transistor ye-field-effect. Ifilimu ye-MoS2 kwezi zakhiwo isebenze njengejelo le-semiconductor. I-conductivity yayo yayilawulwa ngokutshintsha isalathiso se-polarization ye-ferroelectric layer. Xa udibana ne-MoS2, i-La:(HfO2-ZrO2) imathiriyeli, eyathi yaphuhliswa ngaphambili kwilebhu ye-MIPT, yafunyaniswa ine-polarization eshiyekileyo emalunga ne-18 microcoulombs kwisikwere sesentimitha. Ngonyamezelo olutshintshayo lwemijikelo ezizigidi ezi-5, iye yagqwesa kwirekhodi yehlabathi yangaphambili ye-100,000 yemijikelo yeejelo zesilicon.