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The oxygen deficiency-rich TiO 2 /oxygen deficiency-poor TiO 2 stacking structure grown by mist chemical vapor deposition method is used as resistive switching layers of resistive random access memory. Three different annealing temperatures of 500, 600, and 700oC are used to grow the oxygen deficiency-poor TiO 2. The experimental results indicate that the resistances of the oxygen deficiency-rich TiO 2 /oxygen deficiency-poor TiO 2 and the single-layer TiO 2 resistive random access memories are switchable by forming and rupturing the filament paths which are composed of oxygen deficiencies. The number of the filament paths is limited by the oxygen deficiency-poor TiO 2 layer, which improves the memory window and endurance of the resistive random access memory. The stacked structure with the oxygen deficiency-poor TiO 2 which is annealed at 600oC has the largest memory window of 7.8 × 105, endurable switching operation (>103 voltage loops), and long retention time (>104 s). In addition, the current conduction mechanism at the high resistance state of the RRAM with the stacked structure as the resistive switching layer is different from the one using the as-deposited TiO 2 as the resistive switching layer. [ABSTRACT FROM AUTHOR]

This study investigates InSnZnO thin films deposited using mist chemical vapor deposition with different nitrogen (N 2)/oxygen (O 2) ratios of carrier gases. The crystallinity and bandgap of InSnZnO are not affected by the carrier gases; however, the content of the oxygen deficiency of the InSnZnO thin films reduces when the N 2 /O 2 mixed carrier gases have higher oxygen ratio. The InSnZnO thin-film transistor (TFT) shows the highest field-effect mobility (65.04 cm2V−1s−1) when N 2 is used as the carrier gas to deposit the InSnZnO thin film. Although the field-effect mobility of the InSnZnO TFT that uses the N 2 (60 vol%)/O 2 (40 vol%) mixed carrier gas to deposit InSnZnO thin film is the lowest (47.65 cm2V−1s−1), it is still higher than those of the amorphous InGaZnO thin film transistors (∼10 cm2V−1s−1). Furthermore, the InSnZnO TFT using the N 2 (60 vol%)/O 2 (40 vol%) mixed carrier gas to deposit InSnZnO thin film exhibits the steepest subthreshold slope (102 mV/dec), the largest on/off current ratio (4.6 × 107), and the most stable electrical characteristics after the negative bias stress test for 10,800 s. [ABSTRACT FROM AUTHOR]

The p-GaN/N-Mg0.3Zn0.7O:In heterojunction photodiode is demonstrated in this study. The p-type GaN is grown using a hydride vapor phase epitaxy (HVPE) method and the n-type Mg0.3Zn0.7O:In thin film is deposited using a mist atmospheric pressure chemical vapor deposition (MAPCVD) method. The p-GaN/N-Mg0.3Zn0.7O:In photodiode shows a significant rectification ratio of $2.3 \times 10^{6}$ and high maximum responsivity of 0.93 A/W to UV-B. The significant UV-B to UV-A and UV-A to visible rejection ratios are found in the photodiode, which suggests that the p-GaN/N-Mg0.3Zn0.7O:In photodiode is capable of identifying visible light, UV-A, and UV-B. [ABSTRACT FROM AUTHOR]

This study investigates heterojunction thin-film transistors (HTFTs) with Mg $_{X}$ Zn $_{1- {X}}\text{O}$ /zinc oxide (ZnO) heterojunctions deposited using mist chemical vapor deposition (mist-CVD). The X-ray diffraction patterns indicate that the mist-CVD deposited Mg $_{X}$ Zn $_{1- {X}}\text{O}$ /ZnO heterojunctions are ${c}$ -axis oriented. Different Mg/Zn ratios (0.1/0.9, 0.2/0.8, and 0.3/0.7) and Mg $_{X}$ Zn $_{1- {X}}\text{O}$ thickness (15, 30, 45 nm) are used to form the Mg $_{X}$ Zn $_{1- {X}}\text{O}$ /ZnO heterojunctions of HTFTs. The Mg0.3Zn0.7O (15 nm)/ZnO HTFT exhibits high field-effect mobility of 165.56 cm2V−1s−1 and steep subthreshold slope (SS) of 106 mV/dec, but low ON-/OFF-current ratio and high gate leakage current. The Mg0.3Zn0.7O (45 nm)/ZnO HTFT shows the largest ON-/OFF-current ratio of $8.4\times10$ 8 and low gate leakage current of 19.4 pA (at ${V}_{G} =5$ V)/0.27 pA (at ${V}_{G} = -5$ V) but sacrifices the field-effect mobility and SS. The Mg0.3Zn0.7O (30 nm)/ZnO HTFT with the optimum electrical characteristics is used to estimate the stability. It is found that the Mg0.3Zn0.7O/ZnO HTFT is more stable than the ZnO thin-film transistor (TFT). [ABSTRACT FROM AUTHOR]

The 5-nm-thick Mg0.05Sn0.95Ox thin film deposited using mist chemical vapor deposition is used as a channel layer of the thin-film transistor (TFT). Mg0.05Sn0.95Ox improves the crystallinity, reduces the number of oxygen deficiencies, and enlarges the energy bandgap compared with SnO2. Mg0.05Sn0.95Ox-based TFT shows higher field-effect mobility (144.9 cm2V−1s−1), steeper subthreshold slope (134 mV/decade), and significant ON/OFF current ratio (>109) than the SnO2-based TFT. Owing to fewer oxygen-related defects, wide energy bandgaps, and stable Mg-O chemical bonding, the Mg0.05Sn0.95Ox-based TFT exhibits more stable electrical performance than the SnO2 TFT after negative bias illumination stress testing. These results suggest that Mg0.05Sn0.95Ox is a promising material for high electron mobility TFT applications. [ABSTRACT FROM AUTHOR]

This study uses mist atmospheric pressure chemical vapor deposition with deposition/annealing cyclic method to grow c-axis aligned crystalline (CAAC) InGaZnO. The material characteristics of the CAAC-InGaZnO are analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, photoluminescence, and an ellipsometer to determine the crystal structure, oxygen deficiency, trap energy level, and energy bandgap. The CAAC-InGaZnO thin-film transistor (TFT) shows better electrical performance than the one based on amorphous InGaZnO, including higher field-effect mobility (90.4 cm2 V−1 s−1), lower OFF-state leakage current (16 pA), steeper subthreshold swing (86 mV/dec), and higher on/off current ratio (>1010). Moreover, the negative bias illumination stress (NBIS) test is used to estimate the stability of the TFT. The threshold voltage of the present CAAC-InGaZnO TFT changes −0.4 V when the TFT is stressed for 10 000 s. [ABSTRACT FROM AUTHOR]

This article proposes an Mg0.35Zn0.65O/Al/ZnO structure, with which photodetectors (PDs) are able to identify ultraviolet (UV)-A (400–320 nm) and UV-B (320–280 nm). Both Mg0.35Zn0.65O and ZnO thin films are deposited using mist atmospheric pressure chemical vapor deposition (MAPCVD) method. At first, the material characteristics such as crystal structure, oxygen deficiency, energy bandgap, and photoluminescence (PL) of Mg0.35Zn0.65O and ZnO thin films are analyzed. The present Mg0.35Zn0.65O/Al/ZnO PD shows UV-B to UV-A rejection ratio of 15 in the spectral responsivity characteristics. Additionally, the detectivity characteristics suggest that the present Mg0.35Zn0.65O/Al/ZnO PD is able to identify UV-A and UV-B. Furthermore, the Mg0.35Zn0.65O/ZnO hetero-interface enhances the carrier mobility which further improves the response time. [ABSTRACT FROM AUTHOR]

This paper presents the GaxZn1−xO (x = 0, 0.1, and 0.3)-based photodetectors (PDs) by using mist atmospheric pressure chemical vapor deposition. X-ray diffraction and X-ray photoelectron spectroscopy are used to characterize crystal orientation, chemical qualitative, and quantitative characteristics of the GaxZn1−x (x = 0, 0.1, and 0.3) thin films. The photoluminescence is used to observe the near-band-edge emission and trap energy level. Among these three PDs, the Ga0.3Zn0.7O-based PD shows the lowest dark current, smallest noise current, and shortest response time. Furthermore, the Ga0.3Zn0.7O-based PD exhibits higher UV-B to UV-A rejection ratio and higher UV-B to visible rejection ratio. It is found that the cutoff wavelength is tunable by changing Ga contents in GaxZn1−x thin films. [ABSTRACT FROM AUTHOR]