A Direct Method to Extract Transient Sub-Gap Density of State (DOS) Based on Dual Gate Pulse Spectroscopy

Abstract

Sub-gap density of states (DOS) is a key parameter to impact the electrical characteristics of semiconductor materials-based transistors in integrated circuits. Previously, spectroscopy methodologies for DOS extractions include the static methods, temperature dependent spectroscopy and photonic spectroscopy. However, they might involve lots of assumptions, calculations, temperature or optical impacts into the intrinsic distribution of DOS along the bandgap of the materials. A direct and simpler method is developed to extract the DOS distribution from amorphous oxide-based thin-film transistors (TFTs) based on Dual gate pulse spectroscopy (GPS), introducing less extrinsic factors such as temperature and laborious numerical mathematical analysis than conventional methods. From this direct measurement, the sub-gap DOS distribution shows a peak value on the band-gap edge and in the order of 1017–1021/(cm3·eV), which is consistent with the previous results. The results could be described with the model involving both Gaussian and exponential components. This tool is useful as a diagnostics for the electrical properties of oxide materials and this study will benefit their modeling and improvement of the electrical properties and thus broaden their applications.

Modeling and Mechanism of Enhanced Performance of In-Ga-Zn-O Thin-Film Transistors with Nanometer Thicknesses under Temperature Stress

“…DOS is an important parameter that impacts the electrical properties of transistors, which indicates the amount of electron traps . Here, Figure a shows the DOS along the band gap of the semiconductor channel In-Ga-Zn-O, which was extracted based on a previously published method .…”

“…DOS is an important that impacts the electrical properties of transistors, which indicates the amount of electron traps. 18 Here, Figure 3a shows the DOS along the band gap of the semiconductor channel In-Ga-Zn-O, which was extracted based on a previously published method. 16 The DOS experiment tested a range of temperature changes from 303 to 343 K. The temperature of the human body belongs to this temperature range, proving that the device has the potential to be used as a human temperature sensor.…”

“…IGZO nanometer-thick TFTs were fabricated as follows . As seen in Figure , a Si substrate and 100 nm SiO 2 were used as the bottom gate and dielectric layer, respectively.…”

“…14−17 ■ EXPERIMENTAL METHODS IGZO nanometer-thick TFTs were fabricated as follows. 18 As seen in Figure 1 the bottom gate and dielectric layer, respectively. An IGZO channel about 40 nm thick was deposited using radiofrequency (RF) magnetron sputtering, with lithographical technologies used to define a channel length and width as 30−120 and 100 μm, respectively.…”

Recent advances in novel graphene: new horizons in renewable energy storage technologies

“…For the past several decades, however, the fast depletion of fossil fuels due to their rising use has shifted the research dominantly to the progress and usage of renewable energy resources, for example wind, tidal, solar energy, and hydrogen. 1–105 Energy storage technologies must be efficient for renewable energies to be broadly used at domestic as well as industrial levels. Portable electric vehicles (EVs) and hybrid electric car applications are being extensively expanded to meet the needs of our information-rich, mobile culture.…”