Plasma Enhanced Atomic Layer Deposition of Silicon Nitride for Two Different Aminosilane Precursors Using Very High Frequency (162 MHz) Plasma Source.

Plasma enhanced atomic layer deposition (PEALD) of silicon nitride (SiN) using very high frequency (VHF, 162 MHz) plasma source was investigated at the process temperatures of 100, 200, and 300 °C. Two aminosilane precursors having different numbers of amino ligands, bis(-butylamino)silane (BTBAS) and di(-butylamino)silane (DSBAS), were used as Si precursors. A comparative study was also conducted to verify the effect of the number of amino ligands on the properties of SiN film.

High-throughput manufacturing of epitaxial membranes from a single wafer by 2D materials-based layer transfer process.

Layer transfer techniques have been extensively explored for semiconductor device fabrication as a path to reduce costs and to form heterogeneously integrated devices. These techniques entail isolating epitaxial layers from an expensive donor wafer to form freestanding membranes. However, current layer transfer processes are still low-throughput and too expensive to be commercially suitable.

Selective etching of silicon nitride over silicon oxide using ClF/H remote plasma.

Precise and selective removal of silicon nitride (SiN) over silicon oxide (SiO) in a oxide/nitride stack is crucial for a current three dimensional NOT-AND type flash memory fabrication process. In this study, fast and selective isotropic etching of SiN over SiO has been investigated using a ClF/H remote plasma in an inductively coupled plasma system. The SiN etch rate over 80 nm/min with the etch selectivity (SiN over SiO) of ~ 130 was observed under a ClF remote plasma at a room temperature.

Deposition of Very-Low-Hydrogen-Containing Silicon at a Low Temperature Using Very-High-Frequency (162 MHz) SiH Plasma.

Low-hydrogen-containing amorphous silicon (a-Si) was deposited at a low temperature of 80 °C using a very high frequency (VHF at 162 MHz) plasma system with multi-split electrodes. Using the 162 MHz VHF plasma system, a high deposition rate of a-Si with a relatively high deposition uniformity of 6.7% could be obtained due to the formation of high-ion-density (>10 cm) plasma with SiH and a lack of standing waves by using small multi-split electrodes.

Impact of 2D-3D Heterointerface on Remote Epitaxial Interaction through Graphene.

Remote epitaxy has drawn attention as it offers epitaxy of functional materials that can be released from the substrates with atomic precision, thus enabling production and heterointegration of flexible, transferrable, and stackable freestanding single-crystalline membranes. In addition, the remote interaction of atoms and adatoms through two-dimensional (2D) materials in remote epitaxy allows investigation and utilization of electrical/chemical/physical coupling of bulk (3D) materials 2D materials (3D-2D-3D coupling). Here, we unveil the respective roles and impacts of the substrate material, graphene, substrate-graphene interface, and epitaxial material for electrostatic coupling of these materials, which governs cohesive ordering and can lead to single-crystal epitaxy in the overlying film.

Ultrasensitive MoS photodetector by serial nano-bridge multi-heterojunction.

The recent reports of various photodetectors based on molybdenum disulfide (MoS) field effect transistors showed that it was difficult to obtain optoelectronic performances in the broad detection range [visible-infrared (IR)] applicable to various fields. Here, by forming a mono-/multi-layer nano-bridge multi-heterojunction structure (more than > 300 junctions with 25 nm intervals) through the selective layer control of multi-layer MoS, a photodetector with ultrasensitive optoelectronic performances in a broad spectral range (photoresponsivity of 2.67 × 10 A/W at λ = 520 nm and 1.

Silicon Nitride Deposition for Flexible Organic Electronic Devices by VHF (162 MHz)-PECVD Using a Multi-Tile Push-Pull Plasma Source.

Depositing a barrier film for moisture protection without damage at a low temperature is one of the most important steps for organic-based electronic devices. In this study, the authors investigated depositing thin, high-quality SiN film on organic-based electronic devices, specifically, very high-frequency (162 MHz) plasma-enhanced chemical vapor deposition (VHF-PECVD) using a multi-tile push-pull plasma source with a gas mixture of NH/SiH at a low temperature of 80 °C. The thin deposited SiN film exhibited excellent properties in the stoichiometry, chemical bonding, stress, and step coverage.

Atomic layer etching of graphene through controlled ion beam for graphene-based electronics.

The electronic and optical properties of graphene are greatly dependent on the the number of layers. For the precise control of the graphene layers, atomic layer etching (ALE), a cyclic etching method achieved through chemical adsorption and physical desorption, can be the most powerful technique due to barely no damage and no contamination. In this study, we demonstrated the ALE process of graphene layers without noticeably damaging the graphene by using a controlled low energy oxygen (O/O)-ion for chemical adsorption and a low energy Ar-ion (11.