Here, we present the first demonstration of an important building block in vdW solids: room temperature Esaki tunnel diodes. The energy band alignment changes from a staggered gap band offset (type‐II) to a broken gap (type‐III) when changing the negative back‐gate voltage to positive, resulting in the device operating as a rectifier diode (rectification ratio ~10 4) or an n‐type tunneling field effect transistor, respectively. A band gap is the distance between the valence band of electrons and the conduction band.Essentially, the band gap represents the minimum energy that is required to excite an electron up to a state in the conduction band where it can participate in conduction. Doping is a vitally important technique that can be used to modulate the properties of two‐dimensional materials. 6, to occur at M and the fundamental band gap of 2.25 eV is between the VBM at Γ and the CBM at L. The valence band is found to be composed of a mixture of S 3p and Sn 5s, while the conduction band consists of a … In this work, by using first‐principles density functional calculations, we investigated the electrical properties of SnSe 2 monolayers by p‐type/n‐type and isoelectronic doping. The band gap of SnSe 2 can be tuned from bulk to few-layer thin films with a wide electromagnetic spectrum range (from 1–2 eV). buffer layer. The band offset from SnSe2 Fermi level to Al2O3 conduction band minimum is found to be 3.3±0.05 eV and SnSe2 is seen to have a high level of intrinsic electron (n-type) doping with the Fermi level positioned at about 0.2 eV above its conduction band minimum. Two-dimensional SnSe 2 has obvious adjustable band gap characteristics. INTRODUCTION The subthreshold slope (SS) in conventional transistors is limited by thermionic Tin selenide multilayer thin films were prepared by successive evaporation of tin and selenium layers. The shift in absorption spectra was observed on SnSe 2 films from UV studies. This makes it an attractive … In this article, we prepared a thin layer of SnSe 2 by electrochemical methods and detected its nonlinear optical characteristics. The direct band gap of 2.77 eV can be seen, in Fig. The calculated gap is in good agreement with the previous calculated result (0.8 eV) , and it is a little larger than the bulk value of 0.71 eV . The optical band gap values of SnSe 2 and … The optical constants n and ? The structure is two-dimensional and consists of one SnSe2 sheet oriented in the (0, 0, 1) direction. We note that, 1T-ZrS 2 monolayer is an indirect gap (1.1 eV) semiconductor ,while 2H-MoSe 2 and 2H-WSe 2 monolayers have direct wide band gaps of 1.44 eV and 1.56 eV, respectively . A valence band offset of 0.8 eV, matches the energy gap of SnSe 2 in such a way that the VB edge of WSe 2 and the CB edge of SnSe 2 are lined up, making this materials combination suitable for (nearly) broken gap 2D-2D TFETs. Sn4+ is bonded to six equivalent Se2- atoms to form edge-sharing SnSe6 octahedra. because of its appropriate indirect band gap (theoretical value of 0.71 eV in bulk material and 0.969 eV monolayer material). of crystalline C6, n-type SnSe2, at 290 and 77 ?K, have been measured over the photon energy range 0?05-3?7 ev. Its thickness can be controlled to keep it on the desired band gap. The X-ray diffraction study reveals that as deposited films (SnSe) have orthorhombic crystal structure while the annealed films (SnSe 2) have hexagonal structure. 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