Vertical oxide thin-film transistor with interfacial oxidation

Abstract

A vertical oxide thin-film transistor was developed with interfacial oxidation for low voltage operation. The gate metal was used as a spacer for the definition of the transistor’s channel as well as the gate electrode. After definition of the vertical side wall, an IGZO (In-Ga-Zn Oxide) layer was deposited, followed by the interfacial oxidation to form a thin gate insulator. Ta was used for the gate material due to the low Gibbs free energy and high dielectric constant of tantalum oxide. A 15 nm tantalum oxide layer was obtained by the interfacial oxidation of Ta at 400 °C under oxygen atmosphere. The thin gate oxide made it possible to operate the transistor under 1 V. The low operation voltage enables low power consumption, which is essential for mobile application.

Research Progress of Vertical Channel Thin Film Transistor Device

“…The V-TFT structure mentioned above utilizes a spacer layer to separate the source and drain electrodes, creating a vertical structure. Additionally, there have been reports of using gate electrodes to replace spacer layers for this purpose [30,31]. As shown in Figure 3a, in the structure proposed by Baek et al [30], the interface between the gate electrode, the source electrode, and the drain electrode has a growing interlayer dielectric (ILD), to block Based on these vertical structures, Ahn et al proposed a trench-type vertical structure [29].…”

“…Additionally, there have been reports of using gate electrodes to replace spacer layers for this purpose [30,31]. As shown in Figure 3a, in the structure proposed by Baek et al [30], the interface between the gate electrode, the source electrode, and the drain electrode has a growing interlayer dielectric (ILD), to block Based on these vertical structures, Ahn et al proposed a trench-type vertical structure [29]. Unlike the mesa structure, in this trench-type vertical structure the source electrode and drain electrode have the same size.…”

“…Additionally, there have been reports of using gate electrodes to replace spacer layers for this purpose [ 30 , 31 ]. As shown in Figure 3 a, in the structure proposed by Baek et al [ 30 ], the interface between the gate electrode, the source electrode, and the drain electrode has a growing interlayer dielectric (ILD), to block the electrical interconnection between metals. This structure does not require the deposition of an additional spacer layer in addition to depositing three types of electrodes.…”

“… ( a ) The vertical structure of the gate electrode as a spacer layer [ 30 ]. ( b ) The active layer itself serves as the vertical structure of the spacer layer [ 32 ].…”

Vertical organic transistors with a permeable base: from fundamentals to performance prediction

“…First, integration density can be substantially improved. If we imagine a case where a standard thin-film transistor is rotated to make a vertical-channel device, 7 the original thickness dimension becomes an in-plane dimension, which should typically consume only a small fraction of the substrate area. Second, the channel length ( L ) can be greatly reduced.…”