Effects of substrate and anode metal annealing on InGaZnO Schottky diodes

Abstract

By studying different annealing effects of substrate and anode metal, high-performance Schottky diodes based on InGaZnO (IGZO) film have been realized. It is observed that a suitable thermal annealing of the SiO 2 /Si substrate significantly improves the diode performance. In contrary, annealing of the Pd anode increases surface roughness, leading to degradation in the diode performance. As such, by only annealing the substrate but not the anode, we are able to achieve an extremely high rectification ratio of 7.2 × 10 7 , a large barrier height of 0.88 eV, and a near unity ideality factor of 1.09. The diodes exhibit the highest performance amongst IGZO-based Schottky diodes reported to date where IGZO layer is not annealed.The capacitance vs. voltage measurements indicate that the surface roughness is correlated with the trap state density at the Schottky interface.

Half-volt operation of IGZO thin-film transistors enabled by ultrathin HfO2 gate dielectric

“…As such, the a-IGZO TFTs exhibit desirable properties as low power devices, including a small subthreshold swing of 75 mV/decade, a low threshold voltage of 0.3 V, and a high on/off current ratio of 8 × 10 6 . Furthermore, even under an ultralow operation voltage of 0.5 V, the on/off ratio was also up to 1 × 10 6 . The electron transport through the HfO2 layer has also been analyzed, indicating the Poole-Frenkel emission and Fowler-Nordheim tunneling mechanisms in different voltage ranges.…”

“…After that, a-IGZO has received much attention because of its excellent performance, including high electron mobility, low off current, excellent uniformity, surface flatness, stability, optical transparency, large-area production, and wide process temperature. 5,6 As such, a-IGZO TFTs have started replacing amorphous-silicon transistors in large-area displays. 7,8 However, large voltages are often needed for a-IGZO TFTs to achieve high mobility and high on/off current ratios.…”

High-Performance Ga2O3 Diode Based on Tin Oxide Schottky Contact

“…The SnOx/Ga2O3 SBD has a very low Ndepl/Ne ratio of 11, indicating very low defect density, and this agrees well with the close-to-unity n of 1.02. The Schottky barrier extracted from the C-V characteristic, ΦB,CV, is 1.34 eV by using [29], where the last term describing the energy gap between the conduction band and Fermi level is deduced to be 0.09 eV, and the conduction band density of states Nc is 5.2×10 18 cm -3 [29]. A close agreement of ΦB,JV (1.17 eV) and ΦB,CV (1.34 eV) indicates that the SnOx/Ga2O3 Schottky contact has relatively high uniformity.…”

Multi frequency multi bit amplitude modulation of spoof surface plasmon polaritons by schottky diode bridged interdigital SRRs

“…And its propagation attenuation is less than 5.5 dB out of the stop band. Compared with simulated results, the central frequencies of both resonant responses have a red shift of about 2.7 GHz due to the dielectric constant of a-IGZO 23 .…”

“…The pink area is a 500-nm amorphous IGZO film with an electron mobility of 10–50 cm 2 /Vs, which was deposited by RF sputtering at room temperature. In addition to the merits of low-temperature fabrication process, large area, high yield, and low cost, amorphous IGZO has found attractive prospects in flexible applications and large-area industrial fabrication 23 – 25 . The transmission line with interdigital SRRs, i.e., Schottky electrode, is composed of 10 nm Ti/300 nm Au/ 50 nm Pd.…”