Modeling and experimental studies of a side band power re-injection locked magnetron

A side band power re-injection locked(SBPRIL) magnetron is presented in this paper. A tuning stub is placed between the external injection locked(EIL) magnetron and the circulator. Side band power of the EIL magnetron is reflected back to the magnetron. The reflected side band power is reused and pulled back to the central frequency. A phase-locking model is developed from circuit theory to explain the process of reuse of side band power in SBPRIL magnetron. Theoretical analysis proves that the side band power is pulled back to the central frequency of the SBPRIL magnetron, then the amplitude of the RF voltage increases and the phase noise performance is improved. Particle-in-cell(PIC) simulation of a 10-vane continuous wave(CW) magnetron model is presented. Computer simulation predicts that the frequency spectrum's peak of the SBPRIL magnetron has an increase of 3.25 d B compared with the free running magnetron. The phase noise performance at the side band offset reduces 12.05 d B for the SBPRIL magnetron. Besides, the SBPRIL magnetron experiment is presented. Experimental results show that the spectrum peak rises by 14.29% for SBPRIL magnetron compared with the free running magnetron. The phase noise reduces more than 25 d B at 45-k Hz offset compared with the free running magnetron.     

5.8GHz磁控管的数值模拟和实验研究

C波段高稳定度磁控管是目前磁控管的研究重点。对5.8GHz磁控管进行模拟研究,冷腔计算磁控管π模频率为5.863GHz,阳极用双端双隔模带结构磁控管的工作频率与相邻模式频率分隔度为44%。模拟磁控管输出频率为5.856GHz,输出微波功率约1.2kW。对研制的磁控管进行注入锁定实验研究,输出微波功率1.047kW,效率约为58%。磁控管锁频锁相后输出的频率和相位稳定。     

新型无线局域网双频段微带贴片天线设计

 新型无线局域网双频段微带贴片天线采用50 Ω微带线进行馈电,采用在贴片切槽设计方式,实现了微带天线在双频段工作的要求。其中心工作频率分别为2.44 GHz和5.20 GHz,相应的工作带宽分别达到了200 MHz和1.20 GHz。该天线具有小尺寸、结构简单、制作简单,低成本和在各工作频点处具有良好的方向性等优点,而且只需简单修改辐射贴片上的缝隙尺寸参数,就可以实现对天线高频段和低频段的调节。     

L波段全腔提取轴向输出相对论磁控管设计

设计了一种全腔提取轴向输出相对论磁控管。在模工作的N腔磁控管中, 该结构利用磁耦合的方式通过两个相邻谐振腔在一个扇形波导内激励起TE11模, 然后再由N/2个相位相同的扇形波导TE11模沿轴向向外传输。对L波段全腔提取轴向输出磁控管进行了仿真设计, 在600 kV, 6.3 kA的条件下, 获得1.89 GW微波输出, 功率转换效率50%, 微波频率1.57 GHz。该结构在径向方向上仅增加一个扇形波导厚度, 便于实现相对论磁控管的紧凑、高效设计。     

Development of protective metal coatings on aluminum by magnetron sputtering

Depositions of copper and titanium coatings on aluminum foils and polished aluminum plates for thier protection against corrosion in alkaline media were performed. The coatings were deposited in three different types of magnetron sputtering systems: a direct current (DC) magnetron discharge, a high current impulse magnetron discharge, and a DC magnetron discharge with melted cathode. Only aluminum foils coated with copper films obtained by combined ion-plasma technology, which included preliminarily sputtering of the aluminum surface with an ion beam, deposition of a dense interlayer in the DC magnetron discharge with ion assistance of initial stage of deposition, and deposition of additional layer in the magnetron discharge with melted cathode, were resistant against 30 wt % NaOH solution.     

相对论磁控管谐振模式的模式分解研究

随着磁控管的发展,磁控管中的模式关系变得愈发复杂,模式间的竞争也愈发激烈。为了更好地进行磁控管的模式研究,基于本征模的正交性,推导并提出了一种模式分解的方法,并以A6型相对论磁控管作为研究对象,对其不同振荡状态下的工作场进行了模式分解的应用。结果表明,相对论磁控管振荡时,将会出现多模共存的现象,且磁控管将会振荡在成分最高的本征模频率上。同时,结果中展现了简并模式同时存在,以同趋势振荡的现象,结合PIC模拟方法,确定了具有径向输出结构的相对论磁控管能够在简并模式振荡的情况下,能够实现稳定的输出。     

双注磁控注入电子枪

为了增加回旋管的功率,采用双注磁控注入电子枪产生相对论电子注。与双阳极磁控注入电子枪相比,双注磁控注入电子枪产生双束电子注,在不影响电子注质量的基础上,增加电子枪的电流;电子枪产生相同电流时,双注磁控注入电子枪电子注电流小,电子注电子之间的空间电荷效应小,能够降低电子注的速度零散,提高电子注的质量。采用MAGIC软件数值模拟双注磁控注入电子枪,设计出一支大束流、低速度零散的双注磁控注入电子枪。     

磁控管衍射输出结构的π模特性

 磁控管结构以及类磁控管结构（无阴极）是具有衍射输出结构的磁控管最基本的组成单元,分析这两种结构的色散关系是研究具有衍射输出结构的磁控管模式转换和传输特性的基础。在基于场匹配法得到类磁控管结构的色散关系的同时,利用数值计算定量分析了6腔和2腔磁控管结构以及类磁控管结构中的π模谐振点随结构参数的变化关系。分析结果表明：对于磁控管结构,当阴阳极间距一定时,π模谐振波数随谐振腔半径的减小而增大;当谐振腔半径一定时,π模谐振波数随阴阳极间距的增大而增大;对于类磁控管结构,π模谐振波数随谐振腔深度的减小或提取腔半径的减小而增大。     

Reactive process and hysteresis effect in magnetron with magnetized hollow cathode enhanced target

The hysteresis effect in the reactive process was investigated in the magnetron with a magnetized hollow cathode enhanced target (HoCET) in which the target is coupled with the hollow cathode magnetized by the magnetic field of the magnetron. The process, where both the magnetron and hollow cathode plasmas are combined, is compared to the magnetron sputtering. The hysteresis curve in the magnetized HoCET magnetron, recording the titanium emission intensity versus varying content of nitrogen in the gas mixture exhibits a local maximum on the increasing part of the curve. The hysteresis curve is shifted to lower contents of nitrogen than the hysteresis curve for the magnetron. It is concluded that more efficient utilization of the reactive gas takes place in this device.     

阻抗匹配条件下磁控管的注入锁频

单只磁控管输出功率不能满足大规模工业应用, 需要对多只磁控管进行相干功率合成. 为解决普通磁控管相干功率合成所需的相位一致性, 需要对普通磁控管引入注入锁频技术, 以保障工作频率和相位差的稳定性. 本文在阻抗匹配的条件下, 结合磁控管稳定振荡的条件, 从等效电路的角度出发对磁控管注入锁频原理进行分析, 给出了在小注入比和大注入比情况下磁控管的注入锁频理论, 大注入比情况比小注入比情况给出了更大的锁频带宽. 采用MATLAB对理论方程进行解析求解, 同时通过三维粒子仿真软件对锁频理论进行了对比验证, 得出了在不同注入比下磁控管的锁频带宽和相位差微分方程, 给出了在不同初始相位下的相位差变化曲线, 得到了A6磁控管在自由振荡和注入锁频工作下三维模拟仿真的输出功率、频率和波形. 模拟结果表明, 在两种情形预测的锁频带宽内, 磁控管均能被锁定并稳定工作, 在大注入比下大注入比情况比小注入比情况更为准确. 关键词： 磁控管 注入锁频 注入比 相位差     

Properties of Low Pressure Magnetron Discharge Under the Initiation of Emission Processes on Discharge Electrodes by An Accelerated Ion Beam

Russian Physics Journal - The effect of an ion beam injected along the axis of the anode electrode of a planar magnetron on the ignition of an anomalous low-pressure glow discharge in the magnetron...     

Algorithms for optical control of reactive magnetron deposition of film coatings

Algorithms for optical control of a reactive gas flow rate are considered for processes of magnetron deposition of film coatings. The algorithms are based on registration of spectral elements (lines, bands) of a cathode material and reactive/inert gases in magnetron discharge plasma spectra. The influence of instabilities in the magnetron discharge power and vacuum chamber pressure on the composition of the deposited flow and gaseous medium was studied for titanium oxide and nitride deposition that were carried out using various algorithms for optical control of the reactive gas flow rate.     

Analysis and experiments of self-injection magnetron

Magnetrons are widely used in microwave-based industrial applications, which are rapidly developing. However, the coupling between their output frequency and power as well as their wideband spectra restricts their further application. In this work, the output frequency and power of a magnetron are decoupled by self-injection. Moreover, the spectral bandwidth is narrowed, and the phase noise is reduced for most loop phase values. In order to predict the frequency variation with loop phase and injection ratio, a theoretical model based on a circuit equivalent to the magnetron is developed. Furthermore,the developed model also shows that the self-injection magnetron is stabler than the free-running magnetron and that the magnetron's phase noise can be reduced significantly for most loop phase values. Experimental results confirm the conclusions obtained using the proposed model.     

Study of a dc magnetron discharge by using a movable grid anode

A method is proposed for determining the density of the ionizing electron component in a dc magnetron discharge in the region where the magnetic field is strong and highly nonuniform. The method is based on the analysis of the measured dependence of the discharge current on the distance between the cathode and the grid anode. The method was used to study the parameters of a magnetron discharge in a process magnetron operating in the regime with a narrow discharge region localized close to the cathode surface.     

Magnetron discharge in an argon-oxygen mixture for deposition of a titanium oxide film

A discharge in a planar magnetron with a titanium target is studied. It is found that a pressure rise from 2 to 6 mTorr in argon at a constant current increases the intensity of excited argon ion lines by almost 20%. The excitation of neutral titanium atoms is independent of the argon pressure: it depends on only the discharge current. The current-voltage characteristic of the magnetron in an argon-oxygen mixture completely reflects processes proceeding on the target of the magnetron.     

Diocotron instability in an annular sheath of a gas-discharge nonneutral electron plasma

The diocotron instability influence on the value of average electron density in a discharge with crossed electric and magnetic fields has been studied in magnetron and inverted magnetron geometries. The obtained results is in agreement with experimental data. It is found that in magnetron with a thin cathode the mode l=1 is unstable in a narrow interval of electron densities. The width of this interval vanishes when the cathode radius tends to zero.     

相对论磁控管透明阴极技术作用机理研究

透明阴极技术对相对论磁控管振荡启动过程具有显著影响,但其加速启动过程的作用机理仍有待深入研究。对采用扇形单元透明阴极的L波段相对论磁控管进行数值模拟,分析了场分布模式和带电粒子空间运动规律,发现透明阴极与实心阴极在磁控管振荡启动过程的差异。可见透明阴极带来的静电场角向分量与外加轴向磁场引起的洛伦兹力,对初始工作状态的电子具有向阳极加速漂移的作用。采用透明阴极的相对论磁控管的电子轮辐外缘更贴近阳极,群聚电子在轴向上具有随距离连续变化的速度分布,使得电子与高频电磁场的能量交换更加充分。对扇形阴极单元的个数与张角组合的匹配效果进行了模拟,给出了磁控管振荡建立阶段静电场角向分量对阴极电子发射与漂移运动的作用规律。透明阴极的设计需要与磁控管慢波结构相匹配,以得到最优化的工作状态。     

一种5.8 GHz磁控管粒子模拟

 借助3维粒子仿真软件对一种新型18叶片5.8 GHz磁控管进行了动态模拟,比较了爆炸式发射与电子注发射的不同。利用磁路电子注发射方式针对不同的阴极发射电流进行了动态模拟,得到了不同发射电流条件下磁控管的工作特性。同时,利用FEMM仿真软件对磁控管磁路进行了仿真,得到了磁控管互作用空间的磁场分布,并在此基础上,对非均匀磁场下磁控管动态性能进行了模拟。     

Modifications of a relativistic magnetron

Experimental studies of relativistic magnetron microwave oscillators aimed at improving the efficiency and stability of microwave pulses are reported. To this end, the basic units of the magnetron, namely, the anode assembly, microwave radiation output device, antenna system, and cathode assembly, are considerably modified.     

Sputtering of the magnetron diode target in the presence of an external ion beam

The effect of an external ion beam on the plasma and target of a dc magnetron sputtering system in the course of reactive deposition of films is investigated. A combined experimental setup consisting of a magnetron diode and a hall-current ion source is constructed. The influence of a fast ion beam on the discharge current formation, the target emission characteristics, and the target etching rate is considered. It is shown that the ion assistance expands the operating range of the magnetron diode, increases the deposition rate, and substantially shortens the target training time. At the same time, it practically does not affect the ionization processes in the plasma.