AIP Advances最新文献_第10页

Enhancing device characteristics of pentacene-based organic transistors through graphene integration: A simulation study and performance analysis 通过石墨烯集成增强基于五碳烯的有机晶体管的器件特性：模拟研究与性能分析

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-09 DOI: 10.1063/5.0218617

Manish Kumar Singh, Kadiyam Anusha, A. D. D. Dwivedi

Transistors find application within various integrated circuits (ICs) alongside a multitude of electronic devices. These ICs have become integral components in contemporary systems. When organic semiconducting materials constitute the active layer, transistors are termed “organic transistors.” The enhancement of diverse device characteristics is achievable through the modeling and simulation of these organic transistors. This study focuses on the simulation of different configurations of pentacene-based organic transistors. To augment device performance, an active layer comprising pentacene is coupled with 5 and 15 nm graphene. Notably, the top gate configuration yields an increase in ON/OFF ratio from 102 to 107, accompanied by an enhancement in sub-threshold swing from 276 to 59 mV/decade. Similarly, the bottom gate configuration exhibits an ON/OFF ratio improvement from 105 to 109, alongside a sub-threshold swing enhancement from 108 to 59 mV/decade. Leveraging graphene as the active layer material results in substantial benefits. These encompass a heightened on-current of 210 mA, a reduced sub-threshold swing of 58 mV/decade, and a significantly enhanced ON/OFF ratio of 1017.

晶体管被应用于各种集成电路（IC）和众多电子设备中。这些集成电路已成为当代系统不可或缺的组成部分。当有机半导体材料构成有源层时，晶体管被称为 "有机晶体管"。通过对这些有机晶体管进行建模和仿真，可以提高器件的各种特性。本研究的重点是模拟基于五碳烯的有机晶体管的不同配置。为了提高器件性能，由五碳烯组成的活性层与 5 纳米和 15 纳米石墨烯耦合。值得注意的是，顶部栅极配置的导通/关断比从 102 增加到 107，同时阈下摆幅从 276 增加到 59 mV/decade。同样，底部栅极配置的导通/关断比从 105 提高到 109，同时阈下摆幅从 108 提高到 59 mV/decade。利用石墨烯作为活性层材料带来了巨大的好处。这些优势包括导通电流提高到 210 mA，亚阈值摆幅降低到 58 mV/decade，导通/关断比显著提高到 1017。

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引用次数: 0

Effect of driving current profile on acceleration efficiency of electromagnetic railgun 驱动电流曲线对电磁轨道炮加速效率的影响

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-08 DOI: 10.1063/5.0214320

Dipjyoti Balo Majumder, Rishi Verma, J. M. V. V. S. Aravind, J. N. Rao, Manraj Meena, Lakshman Rao Rongali, Bijayalaxmi Sethi, Archana Sharma

In this paper, the effect of driving current profile on efficient utilization and conversion of stored electrical energy into kinetic energy of the projectile has been investigated for electromagnetic railgun systems. It has been experimentally evidenced and also corroborated by simulation results that the acceleration efficiency of railgun launcher is much higher for the case when the driving current feed has an over-damped unidirectional profile vs the case when an under-damped sinusoidal current of same amplitude is fed. To analyze this effect, a mathematical model has been developed incorporating dynamic resistance scaling and velocity dependent frictional effects. For the typical case of projectile weighing ∼8 g and input driving current amplitude of ∼220 kA, the estimated average force from the mathematical model simulation acting on the armature projectile increases from 1.4 to 3.83 kN, consequently resulting in an increase in velocity from 489 to 931 m/s and overall efficiency from 0.55% to 2% for the sinusoidal and unidirectional current profiles, respectively. Experimentally, a maximum velocity of ∼1024 m/s was obtained when a unidirectional over-damped current of similar amplitude was fed using a pulse shaping inductor in conjunction with a crowbar switch. The obtained experimental results of trials with different masses of armatures complement the results of the conceived mathematical model used in simulations. The marginal underestimation of the simulated velocity is due to the inevitable lacking in precise estimation of the frictional force and mass loss that dynamically occur in the projectile during acceleration.

本文研究了电磁轨道炮系统的驱动电流剖面对有效利用存储电能并将其转化为弹丸动能的影响。实验和模拟结果都证明，当馈入的驱动电流为过阻尼单向电流时，轨道炮发射器的加速效率要比馈入相同振幅的欠阻尼正弦电流时高得多。为了分析这种效应，我们建立了一个数学模型，其中包含动态阻力缩放和速度相关摩擦效应。在弹丸重量为 ∼8 g 和输入驱动电流振幅为 ∼220 kA 的典型情况下，数学模型模拟估算的作用在电枢弹丸上的平均力从 1.4 kN 增加到 3.83 kN，从而导致速度从 489 m/s 增加到 931 m/s，正弦和单向电流曲线的总效率分别从 0.55% 增加到 2%。实验结果表明，当使用脉冲整形电感和撬棒开关馈入类似振幅的单向过阻尼电流时，最大速度可达 ∼1024 m/s。不同质量电枢的试验结果与模拟所用数学模型的结果相辅相成。模拟速度被略微低估的原因是对加速过程中弹丸动态产生的摩擦力和质量损失缺乏精确的估计。

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引用次数: 0

Optimal energy scheduling for microgrid based on GAIL with Wasserstein distance 基于 GAIL 和 Wasserstein 距离的微电网优化能源调度

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-08 DOI: 10.1063/5.0207444

Kuo Wang, Zhanqiang Zhang, Keqilao Meng, Pengbing Lei, Rui Wang, Wenlu Yang, Zhihua Lin

Owing to the volatility and intermittency of renewable energy generation units in microgrids, effective energy scheduling methods are essential for efficient renewable energy utilization and stable microgrid operation. In recent years, microgrid energy optimization scheduling based on deep reinforcement learning (DRL) has made significant progress. With the development of the microgrid, the drawbacks of the traditional DRL agent, such as long training time and poor convergence effect, are gradually revealed. This paper proposes a generative adversarial imitation learning method with Wasserstein distance for optimal energy scheduling in the microgrid. This method combines a proximal policy optimization algorithm to optimize energy scheduling and reduce microgrid operating costs. First, the agent adaptively learns the action exploration process by imitating expert trajectories. Second, based on the generative adversarial theory, a discriminator network is added, and the Wasserstein distance is introduced into the discriminator network to distinguish between the generative and expert strategies. This feedback assists in updating the neural network parameters. Finally, the effectiveness of the proposed method is verified through an arithmetic example analysis.

由于微电网中可再生能源发电机组的波动性和间歇性，有效的能量调度方法对于高效利用可再生能源和微电网的稳定运行至关重要。近年来，基于深度强化学习（DRL）的微电网能量优化调度取得了显著进展。随着微电网的发展，传统 DRL 代理训练时间长、收敛效果差等缺点逐渐暴露出来。本文针对微电网的最优能量调度，提出了一种具有 Wasserstein 距离的生成式对抗模仿学习方法。该方法结合近似策略优化算法来优化能源调度，降低微电网运行成本。首先，代理通过模仿专家轨迹自适应地学习行动探索过程。其次，基于生成对抗理论，添加一个判别网络，并在判别网络中引入瓦瑟斯坦距离，以区分生成策略和专家策略。这种反馈有助于更新神经网络参数。最后，通过算例分析验证了所提方法的有效性。

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引用次数: 0

Contributions to the isothermal compressibility coefficient of water near the temperature of 42 °C 水在温度 42 °C 附近的等温压缩系数的贡献

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-08 DOI: 10.1063/5.0205612

Leonid A. Bulavin, Yevgenii G. Rudnikov, Alexander V. Chalyi

Using modern databases, the behavior of the isothermal compressibility coefficient −(∂V/∂P)T = VβT of water in the liquid state near its specific temperature of θ = 42.2 ± 0.2 °C was analyzed. The applicability of the principle of corresponding states in a wide range of thermodynamic parameters of water has been confirmed, excluding the area of water anomalies. The following anomalies of the physical–chemical properties of water were observed: (a) the temperature of θ = 42.2 ± 0.2 °C was found at which the entropy contribution to the isothermal compressibility coefficient of water changed its sign and became positive below this temperature; (b) the temperature of θ = 28.8 ± 0.2 °C was found at which the energy contribution to the isothermal compressibility coefficient of water changed its sign and became negative below this temperature; and (c) the temperature of θ = 17.6 ± 0.2 °C was found at which the energy and entropy contributions to the isothermal compressibility coefficient of water were equal. The entropy contribution to the isothermal compressibility coefficient, according to the two-structure model of water, can be associated with the existence of an “expanded” low-density water structure of hydrogen bonds, the role of which increases with decreasing temperature. We associate the energy contribution to the isothermal compressibility coefficient with the “collapsed” high-density water structure of hydrogen bonds, the role of which in the field of thermodynamic anomalies of water decreases as the temperature decreases.

利用现代数据库，分析了液态水在其特定温度θ = 42.2 ± 0.2 °C附近的等温压缩系数-(∂V/∂P)T = VβT的行为。除水异常区域外，相应状态原理在水的广泛热力学参数中的适用性已得到证实。观察到水的物理化学特性存在以下异常：(a) 在 θ = 42.2 ± 0.2 °C 的温度下，水的等温压缩系数的熵值改变了符号，在该温度以下变为正值；(b) 在 θ = 28.8 ± 0.2 °C 时，水的等温可压缩性系数的能量贡献改变了符号，在该温度以下变为负值；以及(c) θ = 17.6 ± 0.2 °C 时，水的等温可压缩性系数的能量贡献和熵贡献相等。根据水的双结构模型，等温压缩系数的熵贡献与氢键 "扩展 "的低密度水结构的存在有关，其作用随着温度的降低而增加。我们将等温压缩系数的能量贡献与氢键的 "塌缩 "高密度水结构联系起来，这种结构在水的热力学异常领域中的作用随着温度的降低而减小。

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引用次数: 0

Simulation study on the influence of initial density distribution of laser ionized plasma on the ion extraction characteristics 激光电离等离子体初始密度分布对离子萃取特性影响的模拟研究

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-08 DOI: 10.1063/5.0206433

Xing Chen, Xiao-Yong Lu, Lu Cai

In isotope concentration technology, ion extraction current and ion extraction efficiency are the key factors to measure the efficiency of the isotope concentration. In order to increase the ion extraction current, researchers usually hope to produce a plasma source with large initial peak density and width; however, in reality, it is limited by the laser power, and the total number of ions in a plasma produced by laser ionization is almost certain. In this case, how to improve the ion extraction efficiency by choosing the appropriate initial density distribution of plasma has become a difficult problem. In this paper, the effects of the initial density distribution of plasma on the ion extraction characteristics are studied by using the electron equilibrium fluid model. The numerical results suggest that the ion extraction efficiency is independent of the initial density distribution of plasma while the total number of ions in the plasma, the distance between the electrodes, and the electric field intensity are kept constant. When the total number of ions and the electric field intensity are kept constant, the distance between the electrodes is shortened by one time, and the time of ion extraction is also shortened by nearly one time; thus, the plasma source with high initial peak density and small width can be chosen, and the aim of ion extraction can be achieved by shortening the distance between the electrodes. This research results provide an important reference for guiding the experimental parameters such as laser power distribution and the design of ion extraction device.

在同位素浓缩技术中，离子萃取电流和离子萃取效率是衡量同位素浓缩效率的关键因素。为了提高离子萃取电流，研究人员通常希望产生一个初始峰值密度和宽度都很大的等离子体源；但实际上，它受到激光功率的限制，激光电离产生的等离子体中离子的总数几乎是确定的。在这种情况下，如何通过选择合适的等离子体初始密度分布来提高离子萃取效率就成了一个难题。本文利用电子平衡流体模型研究了等离子体初始密度分布对离子萃取特性的影响。数值结果表明，在等离子体中离子总数、电极间距和电场强度保持不变的情况下，离子萃取效率与等离子体的初始密度分布无关。当离子总数和电场强度保持不变时，电极间距缩短1倍，离子萃取时间也缩短近1倍；因此，可以选择初始峰值密度高、宽度小的等离子体源，通过缩短电极间距达到离子萃取的目的。该研究成果为指导激光功率分配等实验参数和离子萃取装置的设计提供了重要参考。

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引用次数: 0

A new bilevel algorithm for UUV global path planning 用于 UUV 全局路径规划的新型双级算法

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-08 DOI: 10.1063/5.0207107

Xin Pan, Guoli Feng, Lin Huang, Haiyan Zeng

Global path planning is one of the key technologies in unmanned underwater vehicle (UUV) intelligent control. At present, research on UUV global path planning technology tends to choose long-distance and large-scale 3D space as the research environment, which leads to a sharp increase in the amount of data and search range for 3D spatial path planning. Therefore, an efficient and relatively small data volume 3D spatial path planning method is an urgent problem that needs to be solved for UUV engineering applications. To solve this problem, a new bilevel path planning algorithm for UUV is proposed. In the upper level of the algorithm, a Max Min Ant System-Elite Genetic (MMAS-EGA) algorithm is put forward, which is a hybrid ant colony optimization/genetic algorithm, in order to improve the convergence speed of the algorithm. In the lower level of the bilevel algorithm, a function optimization algorithm and the MMAS algorithm are used to minimize the number of variables to be optimized. To verify the effectiveness of the algorithm, we conducted simulation experiments in a three dimensional environment. The simulation results in the three-dimensional environment show that, compared with the existing bilevel algorithm, the time to search the global optimal solution is reduced by 9%, and the number of iterations is reduced by 4.4%. Furthermore, the new algorithm we proposed is more efficient and suitable for global path planning for different tasks.

全局路径规划是无人潜航器（UUV）智能控制的关键技术之一。目前，无人潜航器全局路径规划技术的研究往往选择长距离、大尺度的三维空间作为研究环境，导致三维空间路径规划的数据量和搜索范围急剧增大。因此，一种高效且数据量相对较小的三维空间路径规划方法是 UUV 工程应用亟待解决的问题。为解决这一问题，本文提出了一种新的 UUV 两级路径规划算法。在算法的上层，提出了最大最小蚁群系统-精英遗传（MMAS-EGA）算法，这是一种蚁群优化/遗传混合算法，目的是提高算法的收敛速度。在双层算法的下层，采用函数优化算法和 MMAS 算法，以最小化待优化变量的数量。为了验证算法的有效性，我们在三维环境中进行了仿真实验。三维环境下的仿真结果表明，与现有的双层算法相比，搜索全局最优解的时间缩短了 9%，迭代次数减少了 4.4%。此外，我们提出的新算法更加高效，适用于不同任务的全局路径规划。

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引用次数: 0

Analysis of the impact of electromagnetic fields on UAV flight control systems in EHV–UHV DC overhead transmission lines 超高压-超高压直流架空输电线路中电磁场对无人机飞行控制系统的影响分析

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-08 DOI: 10.1063/5.0225258

Jie Li, Lingkai Kong, Minghao Chu

The impact of operating voltage on Unmanned Aerial Vehicle (UAV) inspection and control is mainly manifested as electromagnetic interference, where the electric field mainly affects the distribution of space charges and ions, exhibiting adsorption effects on UAVs, and the magnetic field interferes with airborne magnetometers, disrupting the navigation system of UAVs. Under power frequency conditions, the electromagnetic field of alternating current exhibits alternating characteristics, and it only polarizes near the wire to form space charges or ion currents, with little effect at further distances. However, the variation in the magnetic field in one cycle is zero (positively correlated with alternating current), so its impact on UAVs is not particularly significant. Under direct current conditions, a constant current is introduced into the wire, and the electric field polarized around the wire generates a constant property of charge or ion current, resulting in a relatively larger electric field strength and a wider range of influence. At the same time, the constant current generates a constant magnetic field, which is applied to the airborne magnetometer, equivalent to adding a constant interference source, thus having a significant impact on the inspection and control of UAVs. This article uses ANSYS software to conduct electromagnetic field simulation analysis on DC transmission lines of different voltage levels.

工作电压对无人飞行器（UAV）检测和控制的影响主要表现为电磁干扰，其中电场主要影响空间电荷和离子的分布，对无人飞行器产生吸附作用，磁场干扰机载磁力计，破坏无人飞行器的导航系统。在工频条件下，交流电的电磁场呈现交变特性，它只在导线附近极化，形成空间电荷或离子电流，在更远的距离上影响不大。不过，磁场在一个周期内的变化为零（与交流电呈正相关），因此对无人机的影响不是特别大。在直流电条件下，导线中引入恒定电流，导线周围极化的电场会产生恒定性质的电荷或离子电流，因此电场强度相对较大，影响范围也更广。同时，恒定电流产生恒定磁场，施加到机载磁强计上，相当于增加了一个恒定干扰源，从而对无人机的检测和控制产生重大影响。本文使用 ANSYS 软件对不同电压等级的直流输电线路进行电磁场仿真分析。

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引用次数: 0

NeuroRoots, a bio-inspired, seamless brain machine interface for long-term recording in delicate brain regions. 神经根（NeuroRoots）是一种受生物启发的无缝脑机接口，用于在精细脑区进行长期记录。

IF 1.4 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-07 eCollection Date: 2024-08-01 DOI: 10.1063/5.0216979

Marc D Ferro, Christopher M Proctor, Alexander Gonzalez, Sriram Jayabal, Eric Zhao, Maxwell Gagnon, Andrea Slézia, Jolien Pas, Gerwin Dijk, Mary J Donahue, Adam Williamson, Jennifer Raymond, George G Malliaras, Lisa Giocomo, Nicholas A Melosh

Scalable electronic brain implants with long-term stability and low biological perturbation are crucial technologies for high-quality brain-machine interfaces that can seamlessly access delicate and hard-to-reach regions of the brain. Here, we created "NeuroRoots," a biomimetic multi-channel implant with similar dimensions (7 μm wide and 1.5 μm thick), mechanical compliance, and spatial distribution as axons in the brain. Unlike planar shank implants, these devices consist of a number of individual electrode "roots," each tendril independent from the other. A simple microscale delivery approach based on commercially available apparatus minimally perturbs existing neural architectures during surgery. NeuroRoots enables high density single unit recording from the cerebellum in vitro and in vivo. NeuroRoots also reliably recorded action potentials in various brain regions for at least 7 weeks during behavioral experiments in freely-moving rats, without adjustment of electrode position. This minimally invasive axon-like implant design is an important step toward improving the integration and stability of brain-machine interfacing.

具有长期稳定性和低生物扰动的可扩展电子脑植入物是实现高质量脑机接口的关键技术，这种接口可以无缝接入大脑的精细和难以触及的区域。在这里，我们创造了 "NeuroRoots"，一种生物仿真多通道植入体，其尺寸（7 微米宽，1.5 微米厚）、机械顺应性和空间分布与大脑中的轴突相似。与平面柄植入物不同，这些装置由许多独立的电极 "根 "组成，每个卷须相互独立。基于市场上可买到的设备，一种简单的微尺度给药方法在手术过程中对现有神经结构的扰动最小。NeuroRoots 能够在体外和体内对小脑进行高密度单单元记录。在对自由活动的大鼠进行行为实验时，NeuroRoots 还能可靠地记录不同脑区的动作电位至少 7 周，且无需调整电极位置。这种微创轴突状植入设计是提高脑机接口集成度和稳定性的重要一步。

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引用次数: 0

Research on rolling bearing fault diagnosis technology based on singular value decomposition 基于奇异值分解的滚动轴承故障诊断技术研究

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-07 DOI: 10.1063/5.0225222

Jingfang Ji, Jingmin Ge

To solve the difficulty of selecting the number of effective singular values in Singular Value Decomposition denoising, a new method to determine the number of effective singular values is proposed. The proposed method to determine the number of effective singular values is based on the non-zero singular value distribution law of the Hankel matrix constructed by the signal. Specifically, the number of effective singular values in the Hankel matrix is twice the number of frequencies contained in the signal, and the difference between the effective singular values of the noisy signal and the non-zero singular values of the pure signal is very small. The proposed method for determining the number of effective singular values is to perform differential processing on the singular values of the signal and normalize the difference obtained. An empirical parameter T is provided, and the number of effective singular values is determined by comparing them with the normalized results. The proposed method is applied to the simulated and measured rolling bearing signals, and the results are compared with the wavelet threshold denoising method. The results show that the proposed method for determining the number of singular values can effectively filter out the noise frequency contained in the signal while maintaining the characteristic frequency of the signal and achieving the purpose of mechanical equipment fault diagnosis.

为了解决奇异值分解去噪中有效奇异值个数选择的难题，提出了一种确定有效奇异值个数的新方法。所提出的有效奇异值个数确定方法是基于信号构建的汉克尔矩阵的非零奇异值分布规律。具体来说，汉克尔矩阵中的有效奇异值数量是信号所含频率数量的两倍，而噪声信号的有效奇异值与纯信号的非零奇异值之间的差异非常小。所提出的确定有效奇异值数量的方法是对信号的奇异值进行差分处理，并对得到的差值进行归一化处理。提供一个经验参数 T，通过与归一化结果进行比较，确定有效奇异值的数量。将所提出的方法应用于模拟和测量的滚动轴承信号，并将结果与小波阈值去噪方法进行比较。结果表明，所提出的奇异值个数确定方法能有效滤除信号中包含的噪声频率，同时保持信号的特征频率，达到机械设备故障诊断的目的。

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引用次数: 0

Enhancing growth rate in homoepitaxial growth of β-Ga2O3 with flat surface via hydrochloric acid addition in mist CVD 在雾状 CVD 中通过添加盐酸提高具有平坦表面的 β-Ga2O3 的同向外延生长速度

IF 1.6 4区物理与天体物理 Q4 MATERIALS SCIENCE, MULTIDISCIPLINARY

AIP Advances

Pub Date : 2024-08-07 DOI: 10.1063/5.0219242

Ryo Ueda, Hiroyuki Nishinaka, Hiroki Miyake, Masahiro Yoshimoto

Gallium oxide (Ga2O3) is a wide-bandgap oxide semiconductor, with a bandgap of ∼4.9 eV, making it a promising material for power device applications. This study focuses on the effect of hydrochloric acid addition on the growth rate in homoepitaxial growth of β-Ga2O3 using a mist chemical vapor deposition method. For homoepitaxial growth on a (001) β-Ga2O3 substrate, we introduced different concentrations of HCl into the source solution to assess its impact on the growth rate, crystal structures, and surface morphologies of the films. At a growth temperature of 900 °C, HCl addition linearly increased film thickness, enhancing the growth rate by 4.8 times with 9.09 vol. % HCl. No peaks associated with other phases were exhibited by each sample, indicating pure homoepitaxial growth. When comparing samples with similar film thicknesses, the root-mean-square (rms) roughness was enhanced by 1/7 with an increase in the HCl concentration. However, at 800 °C, an increasing solution concentration caused pronounced step bunching and elevated rms roughness, in contrast with the minimal effect observed at 900 °C. In experiments with hydrochloric acid addition at 900 °C, we observed a striped morphology, which maintained consistent rms roughness despite higher temperature.

氧化镓（Ga2O3）是一种宽带隙氧化物半导体，带隙为∼4.9 eV，是一种很有潜力的功率器件应用材料。本研究的重点是采用雾状化学气相沉积法研究盐酸添加量对β-Ga2O3同层外延生长速率的影响。在 (001) β-Ga2O3 基底上进行同向外延生长时，我们在源溶液中引入了不同浓度的盐酸，以评估其对薄膜生长速率、晶体结构和表面形态的影响。在 900 °C 的生长温度下，盐酸的加入线性地增加了薄膜厚度，当盐酸的体积百分比为 9.09 时，生长速度提高了 4.8 倍。每个样品都没有出现与其他相相关的峰值，表明是纯均相外延生长。在比较具有相似薄膜厚度的样品时，均方根（rms）粗糙度随盐酸浓度的增加而增加 1/7。然而，在 800 ℃ 时，溶液浓度的增加会导致明显的阶跃束化和均方根粗糙度的升高，而在 900 ℃ 时则影响甚微。在 900 ℃ 下添加盐酸的实验中，我们观察到了条纹状形态，尽管温度升高，但均方根粗糙度保持一致。

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引用次数: 0