scholarly journals Low-Damage and Self-Limiting (Al)GaN Etching Process through Atomic Layer Etching Using O2 and BCl3 Plasma

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 268
Author(s):  
Il-Hwan Hwang ◽  
Ho-Young Cha ◽  
Kwang-Seok Seo
Keyword(s):  
Photoelectron Spectroscopy ◽  
Schottky Diodes ◽  
Atomic Layer ◽  
Etching Process ◽  
Etching Depth ◽  
Self Bias ◽  
Number Of Cycles ◽  
Etched Surface ◽  
Gan Etching ◽  
Atomic Layer Etching

This paper reports on the use of low-damage atomic layer etching (ALE) performed using O2 and BCl3 plasma for etching (Al)GaN. The proposed ALE process led to excellent self-limiting etch characteristics with a low direct current (DC) self-bias, which resulted in a high linearity between the etching depth and number of cycles. The etching damage was evaluated using several methods, including atomic force microscopy, photoluminescence (PL), and X-ray photoelectron spectroscopy, and the I–V properties of the recessed Schottky diodes were compared with those of digital etching performed using O2 plasma and HCl solution. The electrical characteristics of the recessed Schottky diode fabricated using the proposed ALE process were superior to those of the diodes fabricated using the conventional digital etching process. Moreover, the ALE process yielded a higher PL intensity and N/(Al + Ga) ratio of the etched AlGaN surface, along with a smoother etched surface.

Characterization of Wet Chemical Atomic Layer Etching of InGaAs

2021 ◽  
Vol 314 ◽  
pp. 95-98
Author(s):  
Tomoki Hirano ◽  
Kenya Nishio ◽  
Takashi Fukatani ◽  
Suguru Saito ◽  
Yoshiya Hagimoto ◽  
...  
Keyword(s):  
Surface Condition ◽  
Atomic Layer ◽  
Interface State ◽  
State Density ◽  
Interface State Density ◽  
Etching Process ◽  
Wet Chemical ◽  
Oxide Removal ◽  
Atomic Layer Etching

In this work, we characterized the wet chemical atomic layer etching of an InGaAs surface by using various surface analysis methods. For this etching process, H2O2 was used to create a self-limiting oxide layer. Oxide removal was studied for both HCl and NH4OH solutions. Less In oxide tended to remain after the HCl treatment than after the NH4OH treatment, so the combination of H2O2 and HCl is suitable for wet chemical atomic layer etching. In addition, we found that repetition of this etching process does not impact on the oxide amount, surface roughness, and interface state density. Thus, nanoscale etching of InGaAs with no impact on the surface condition is possible with this method.

scholarly journals Influence of AlN and GaN Pulse Ratios in Thermal Atomic Layer Deposited AlGaN on the Electrical Properties of AlGaN/GaN Schottky Diodes

Coatings ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 489 ◽  
Author(s):  
Hogyoung Kim ◽  
Seok Choi ◽  
Byung Joon Choi
Keyword(s):  
Photoelectron Spectroscopy ◽  
Schottky Diodes ◽  
Charge Trapping ◽  
Negative Temperature ◽  
Atomic Layer ◽  
Algan Layer ◽  
Pulse Ratio ◽  
Current Voltage ◽  
Frenkel Emission ◽  
A Charge

Atomic layer deposited AlGaN with different AlN and GaN pulse ratios (2:1, 1:1, and 1:2) was used to prepare AlGaN/GaN Schottky diodes, and their current transport mechanisms were investigated using current–voltage (I–V) and capacitance–voltage (C–V) measurements. Under low reverse bias condition, the sample with the pulse ratio of 2:1 was explained by Poole–Frenkel emission and the negative temperature dependence for the sample with the pulse ratio of 1:2 was associated with the acceptor levels in the AlGaN layer. Fast interface traps at 0.24–0.29 eV were observed for the samples with the pulse ratios of 1:1 and 1:2, whereas bulk traps at ~0.34 eV were observed for the sample with the pulse ratio of 2:1. Higher trap densities were obtained from the C–V hysteresis measurements when the pulse ratios were 1:1 and 1:2, indicating the presence of a charge trapping interfacial layer. According to the X-ray photoelectron spectroscopy spectra, the pulse ratio of 2:1 was found to have less oxygen-related defects in the AlGaN layer.

scholarly journals Structural and Fluorine Plasma Etching Behavior of Sputter-Deposition Yttrium Fluoride Film

Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 936 ◽  
Author(s):  
Wei-Kai Wang ◽  
Yu-Xiu Lin ◽  
Yi-Jie Xu
Keyword(s):  
Plasma Etching ◽  
Photoelectron Spectroscopy ◽  
Heating Temperature ◽  
Working Pressure ◽  
Etching Depth ◽  
Yttrium Fluoride ◽  
X Ray ◽  
Substrate Heating ◽  
Etching Behavior ◽  
Etched Surface

Yttrium fluoride (YF3) films were grown on sapphire substrate by a radio frequency magnetron using a commercial ceramic target in a vacuum chamber. The structure, composition, and plasma etching behavior of the films were systematically investigated. The YF3 film was deposited at a working pressure of 5 mTorr and an RF power of 150 W. The substrate-heating temperature was increased from 400 to 700 °C in increments of 100 °C. High-resolution transmission electron microscopy (HRTEM) and X-ray diffraction results confirmed an orthorhombic YF3 structure was obtained at a substrate temperature of 700 °C for 2 h. X-ray photoelectron spectroscopy revealed a strongly fluorinated bond (Y–F bond) on the etched surface of the YF3 films. HRTEM analysis also revealed that the YF3 films became yttrium-oxyfluorinated after exposure to fluorocarbon plasma. The etching depth was three times lower on YF3 film than on Al2O3 plate. These results showed that the YF3 films have excellent erosion resistance properties compared to Al2O3 plates.

Vertical Sandwich GAA FETs With Self-Aligned High-k Metal Gate Made by Quasi Atomic Layer Etching Process

2021 ◽  
pp. 1-7
Author(s):  
Yongkui Zhang ◽  
Xuezheng Ai ◽  
Xiaogen Yin ◽  
Huilong Zhu ◽  
H. Yang ◽  
...  
Keyword(s):  
Atomic Layer ◽  
Etching Process ◽  
Metal Gate ◽  
High K ◽  
Atomic Layer Etching

CHF3 and NH3 Additives for Reactive ion Etching of GaAs Using CCl2F2 and SICI4

1991 ◽  
Vol 240 ◽  
Author(s):  
Kuen-Sane Din ◽  
Gou-Chung Chi
Keyword(s):  
Photoelectron Spectroscopy ◽  
Etch Rate ◽  
Reactive Ion Etching ◽  
Experimental Results ◽  
Etching Process ◽  
Ion Etching ◽  
X Ray ◽  
Gaas Wafer ◽  
Self Bias

ABSTRACTTwo fundamental requirements for RIE are the formation of nearly volatile etch products and sufficiently high physical bombardment to remove all substances on the surface. In this study, the GaAs wafer was in-situ pretreated with NH3 or CHF3 plasma prior to actual etching process. The main etchants are CCl2F2 and SiCl4. By adding these additives to the main etch gases, the resulting etch performance was significantly affected. For instance, DC self-bias of CCl2F2 plasma is relatively low and can increase with such gas addition, thus the etching properties related to physical bombardment change too. CHF3 improve GaAs etch rate in CCl2F2through increasing concentration of reactive chlorine-containing species. While CHF3 enhance etch rate in SiCl4 plasma. The as etched samples were examined with X-ray photoelectron spectroscopy. Details of the experimental results will be described.

scholarly journals Gradually Modified Conductance in the Self-Compliance Region of an Atomic-Layer-Deposited Pt/TiO2/HfAlOx/TiN RRAM Device

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1199
Author(s):  
Hojeong Ryu ◽  
Sungjun Kim
Keyword(s):  
Photoelectron Spectroscopy ◽  
Depth Profiling ◽  
Atomic Layer ◽  
High Resistance State ◽  
Long Term Potentiation ◽  
Memory Device ◽  
Bipolar Resistive Switching ◽  
Term Potentiation ◽  
Resistance State ◽  
Neuromorphic System

This study presents conductance modulation in a Pt/TiO2/HfAlOx/TiN resistive memory device in the compliance region for neuromorphic system applications. First, the chemical and material characteristics of the atomic-layer-deposited films were verified by X-ray photoelectron spectroscopy depth profiling. The low-resistance state was effectively controlled by the compliance current, and the high-resistance state was adjusted by the reset stop voltage. Stable endurance and retention in bipolar resistive switching were achieved. When a compliance current of 1 mA was imposed, only gradual switching was observed in the reset process. Self-compliance was used after an abrupt set transition to achieve a gradual set process. Finally, 10 cycles of long-term potentiation and depression were obtained in the compliance current region for neuromorphic system applications.

Sign in / Sign up

Export Citation Format

Share Document