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Boron indium oxide (BIO) is studied for thin-film transistor (TFT) channel layer applications. Sputtered BIO thin films exhibit an amorphous phase over a wide range of B 2 O 3 /In 2 O 3 ratios and remain amorphous up to 500 °C. The band gap decreases linearly with decreasing boron content, whereas device performance generally improves with decreasing boron content. The best amorphous BIO TFT exhibits a field-effect mobility of 10 cm 2 V −1 s −1 , turn-on voltage of 2.5 V, and sub-threshold swing of 0.72 V/dec. Decreasing the boron content to 12.5% leads to a polycrystalline phase, but further increases the mobility up to 20–40 cm 2 V −1 s −1 . TCAD simulation results suggest that the reason for higher performance after increasing the anneal temperature from 200 to 400 °C is due to a lower defect density in the sub-bandgap region of the BIO channel layer.

Single-active layer (SAL) and dual-active layer (DAL) oxide thin-film transistors (TFTs) are fabricated using the same process conditions and compared side by side. The SAL channel consists of amorphous In–Ga–Zn–O (a-IGZO), and the DAL of ultrathin In–Sn–O and a-IGZO. The DAL TFT exhibits strongly improved performance compared to the SAL TFT such as higher mobility of 31 cm $^{\textsf {2}}\cdot \text{V}^{-\textsf {1}}\cdot \text{s}^{-\textsf {1}}$ , smaller subthreshold swing of 175 mV/dec, and better positive bias temperature stress stability. Technology computer-aided design simulation is used to investigate the SAL and DAL device performance. A mapping technique is used to directly correlate the transfer characteristics to the subbandgap density of states. The simulation suggests that the improved performance of the DAL TFT is due to an improved gate insulator/channel interface with an approximately one order of magnitude lower interface trap density.

We describe a process to produce aqueous precursor solutions of the flat-Al13 hydroxo cluster (Al13(μ3-OH)6(μ2-OH)18(H2O)24(NO3)15) via stoichiometric dissolution of bulk Al(OH)3(s) in HNO3(aq). We highlight its facility by demonstrating high yields and large-scale synthesis. X-ray diffraction confirms formation of a single-phase product, and Raman spectra show characteristic O-Al-O vibrational modes, both techniques confirming the identity of the flat-Al13 cluster in the bulk. 27Al NMR spectroscopy and dynamic light scattering also confirm the presence of the cluster in aqueous solution. We show the as-prepared solution produces smooth and continuous thin films via spin-coating. In capacitors, the films exhibit low leakage currents (near 10 nA/cm2) and dielectric constants expected for amorphous Al2O3. Because the precursor preparation requires no postsynthesis purification, it is readily scalable to large volumes.

The production of high-quality thin-film insulators is essential to develop advanced technologies based on electron tunneling. Current insulator deposition methods, however, suffer from a variety of limitations, including constrained substrate sizes, limited materials options, and complexity of patterning. Here, we report the deposition of large-area Al2O3 films by a solution process and its integration in metal-insulator-metal devices that exhibit I- V signatures of Fowler-Nordheim electron tunneling. A unique, high-purity precursor based on an aqueous solution of the nanocluster flat-Al13 transforms to thin Al2O3 insulators free of the electron traps and emission states that commonly inhibit tunneling in other films. Tunneling is further confirmed by the temperature independence of device current.

Objective Burning mouth syndrome (BMS) is a complex of clinical symptoms defined by burning sensations in the oral cavity without observed oral pathology. Clinically two patient groups within BMS were distinguished, one with burning limited to the anterior tongue (glossopyrosis) and the other with burning in multiple mouth regions, including tongue, lips, palate, gums and cheeks (oropyrosis). Biochemical differences between these two groups could assist in distinguishing them. Design Eighty-three patients with BMS, 47 with oropyrosis and 31 with glossopyrosis were studied. Measurements of zinc, copper, magnesium and calcium in blood plasma, erythrocytes and parotid saliva were obtained in patients and in normal subjects and mean levels were compared. Results Clinical history differentiated patients into categories of oropyrosis and glossopyrosis. Erythrocyte and saliva levels of magnesium were significantly lower in patients with glossopyrosis than in patients with oropyrosis or in normal volunteers whereas levels of zinc and calcium were similar. Conclusions These data suggest that patients with glossopyrosis not only differ clinically from those with oropyrosis but also exhibit magnesium deficiency as manifested by lower than normal magnesium levels in saliva and erythrocytes. Lingual burning in patients with glossopyrosis is consistent with hyperalgesia and neurogenic inflammation observed in patients and animals with magnesium deficiency and in magnesium deficient tissues. These results suggest a possible biochemical mechanism for pyrosis in patients with glossopyrosis.