Mesh Bias Controlled Synthesis of TiO₂ and Al_0.74Ti_0.26O₃ Thin Films by Mist Chemical Vapor Deposition and Applications as Gate Dielectric Layers for Field-Effect Transistors

Abstract

The effect of applying a mesh bias during the syntheses of amorphous titanium oxide (a-TiO2) thin films via mist chemical vapor deposition (mist-CVD) was investigated. When a negative bias is applied to the upstream electrode, some of the large mist particles are captured by the mesh electrode, promoting the generation of fine mist particles and increases the number density, resulting in a smooth and dense a-TiO2 network. As a result, the rate of deposition of the a-TiO2 thin films and the surface roughness decreased. The dielectric constant of the a-TiO2 film also increases from 48 to 57.5. These findings suggest that in the synthesis of a-TiO2 films by mist-CVD is promising for promoting the generation of dense a-TiO2 networks and improving the junction properties at the a-TiO2/c-Si interface. Additionally, the effect of applying a mesh bias in the synthesis of amorphous aluminum titanium oxide (a-Al0.74Ti0.26O3) thin alloy films was studied.

Direct synthesis of submillimeter-sized few-layer WS2 and WS0.3Se1.7 by mist chemical vapor deposition and its application to complementary MOS inverter

“…The inset shows the thickness profiles of the samples. Further details of the synthesis of amorphous Al 0.74 Ti 0.26 O y films by mist CVD can be found in recent reports[49,50]. The average size of WS 0.3 Se 1.7 flakes increased to ∼450 µm with a thickness of 1.57 nm (mono/bi layers) at a concentration of 0.01 M l −1 (figureS7).…”

“…Thus, the average size of the atomic mono/bilayer flakes of WS 0.3 Se 1. [49,50]. The average size of WS 0.3 Se 1.7 flakes increased to ∼450 µm with a thickness of 1.57 nm (mono/bi layers) at a concentration of 0.01 M l −1 (figure S7).…”

“…In addition, it has been used to produce various metal oxide, polymer, and TMDC thin films, including Al 2 O 3 , ZnO, CuO, TiO 2 , Al 1−x Ti x O y , and MoS 2 . Thus, it facilitates device fabrication by eliminating the transfer process [38,[49][50][51]. In a previous study, the direct synthesis of few-layer MoS 2 flakes with an average grain size of ∼120 µm from a single precursor of (NH 4 ) 2 MoS 4 using mist-CVD via a sequential mist supply and storage in a closed quartz tube was achieved.…”

A Review on the Progress of Optoelectronic Devices Based on TiO2 Thin Films and Nanomaterials

“…Yokoyama et al investigated the effect of V M on the synthesis of a-TiO 2 and a-Al 0.74 Ti 0.26 O 3 using atmospheric pressure thin-mist chemical vapor deposition (CVD) [ 60 ]. The parameters of the FETs were enhanced using reticular biased a-TiO 2 and a-Al 0.74 Ti 0.26 O 3 films as the gate dielectric layer and mechanically exfoliated bulk single-crystal MoSe 2 .…”

Mist Chemical Vapor Deposition Using Poorly Soluble Particles as Raw Material

“…Mist chemical vapor deposition (mist-CVD) is one of the novel crystal growth techniques with potentially low environmental impact and low cost. Recently, the growth of various metal oxide crystals, such as ZnO-based crystals, [1][2][3][4][5][6][7] MgO-based crystals, [8][9][10] Ga 2 O 3, [11][12][13] and other metal oxides, [14][15][16][17][18][19][20] has been demonstrated by mist-CVD and its related technologies. In addition, similar techniques such as aerosol-assisted CVD (AACVD) have been developed.…”