WX系列崩越二极管

ＷＸ系列崩越二极管ＷＸＳｅｒｉａｌＩＭＰＡＴＴＤｉｏｄｅｓ￥ＣｈｅｎＳｈｕｉｓｈｅｎｇ（ＮａｎｊｉｎｇＥｌｅｃｔｒｏｎｉｃＤｅｖｉｃｅｓＩｎｓｔｉｔｕｔｅ２１００１６）崩越二极管具有优良的性能，在微波及毫米波频段能产生大的连续波或脉冲射频功率，是常用...     

A Small-Signal and Noise Equivalent Circuit for IMPATT Diodes (Short Papers)

A frequency-independent small-signal equivalent circuit for an IMPATT diode is proposed. It incorporates five circuit elements, including a negative resistance, and is valid over an octave range of frequency. With the addition of two white noise sources it also serves as a noise equivalent circuit.     

Broad-Band Characteristics of EHF IMPATT Diodes

Measurements have been made of the oscillator characteristics when a GaAs EHF double-drift IMPATT diode designed for a frequency of 35 GHz is operated over an extended frequency range from 33-50 GHz. The diode which was designed for 35 GHz has a broad-band capability which allows it to produce 2.15 W at 44.1 GHz. An analytic model is shown to predict accurately the observed results. The model indicates that the upper limit in frequency can be increased by reducing the diode area or the series resistance as well as by reducing the length of the drift region.     

IMPATT二极管热阻测试

本文讨论了热阻测试的基本理论;并讨论了如何利用海兹(Hatzi)法选择适当的测试频率测量IMPATT二极管的热阻.利用测试信号频率与热流传播深度的关系可选用不同频率测得管芯热阻或整个器件热阻.并可鉴别管芯焊接质量.本文还用实验验证了测试频率与样品面积的关系.     

Computer-Aided Small-Signal Characterization of IMPATT Diodes

This paper is a discussion of IMPATT wafer small-signal characteristics in the frequency range of 2.0-8.0 GHz. These characteristics have been obtained by computer conversion of reflection phase-gain data. The data handling technique which allows establishment of the desired reference plane and the reduction of the admittance data into the desired equivalent circuit is presented. A calibration procedure using reference impedances consistent with the diode geometry is discussed. The validity of the microwave measurement technique and the data handling process is demonstrated by comparison of the values of junction capacitance determined at microwave frequencies with junction capacitance measurements at 30 MHz. Representative plots are given for wafer conductance and susceptance as a function of frequency with current density as a parameter. In addition, typical values obtained for the circuit elements are presented. These data illustrate the capability of determining package inductance, series resistance as a function of bias voltage, and, with the diode in avalanche, the parallel G, L, and C of the wafer admittance. The diode equivalent circuit was studied as a function of current density to compare results with the existing analytical small-signal theories. This procedure permits the separation of the wafer elements from the parasitic elements of the package. Data obtained from these measurements are extremely useful for ascertaining wafer design parameters and assisting in circuit design.     

Millimeter-Wave CW IMPATT Diodes and Oscillators

This paper summarizes the current state of the art of silicon CW millimeter-wave IMPATT diodes and oscillators in the frequency range from 30 to 250 GHz. Design procedures, fabrication, and packaging technology are reviewed, and the current performance of diode oscillators is reported. A brief account of present device reliability is also presented. The contrast between maturing device technology below 100 GHz and largely laboratory-based technology at higher frequencies is discussed. Finally, a prognosis of future developments is offered.     

崩越二极管模拟分析及实验

应用自编的崩越二极管模拟程序,进行了器件的计算机模拟.给出硅8毫米双漂移崩越管的模拟结果及其分析.并给出经计算机优化器件设计的实验结果.     

高效率砷化镓崩越二极管的并联组合

本文叙述了高效率砷化镓崩越二极管的并联组合技术及多管芯并联器件的热设计;简单介绍了并联器件制造工艺;并给出了两管芯并联的实验结果:在X波段最大输出功率为5.4W,最佳效率达26.6%.     

High Peak Pulse Power Silicon Double-Drift IMPATT Diodes

The performance of high peak pulse power silicon double-drift IMPATT devices operated at medium pulse repetition frequency are discussed. Several devices were characterized and achieved more than 45-W peak pulse power with 10-percent duty cycle at 9.7 GHz. Conversion efficiencies in the order of 9.7-11.2 percent were observed. These results compare with previously reported 19-W peak power, 10-percent duty-cycle, and 9.5-percent efficiency.     

Symmetry Experiments with Four-Mesa IMPATT Diodes (Letters)

Experiments with four-mesa silicon p+-n-n+ IMPATT diodes have shown power saturation and reduced efficiency when connected and packaged in electrically asymmetrical configurations. The need for electrical symmetry is illustrated by experiments wherein seemingly trivial asymmetries caused severe saturation of the power output.     

Effects of Depletion-Layer Modulation on Spurious Oscillations in IMPATT Diodes

A theoretical analysis of the effects of depletion-layer modulation on spurious oscillations in IMPATT diodes is given. The relationship between the magnitude of the depletion-layer modulation, circuit impedance and threshold for degenerate instabilities is presented.     

Theory and Measurement of Back Bias Voltage in IMPATT Diodes

The derivation of the back bias voltage is shown to require carrying the derivation of the Read equation to one order of approximation higher than that which is necessary to obtain the quasi-static result. A new term is shown to be needed in the expression for the back bias voltage which changes its sign to positive under conditions in which the older analyses indicate a negative back bias. Experimental measurements of V/sub bb/ as a function of V/sub RF/ were made using a network analyzer and are in agreement with the new analysis. At frequencies considerably below the range at which our measurements were made, a strong negative back bias voltage is caused by the saturation current.     

Noise in IMPATT diodes: Intrinsic properties

The design of low-noise IMPATT diodes has been aided by theories describing the noise generation under small-signal conditions. A major deficiency in this procedure has existed in that there is no apparent connection between the small-signal behavior and the great increases in the noise observed in large-signal operation. As a remedy a theory has been developed for the noise generation at arbitrary signal levels by using a Read diode model. The theory is based on a linearization technique for calculating the spectrum of homogeneous noise with linear damping resulting in a separation of the large-signal and noise problems. The open-circuit noise voltage increases strongly at high signal levels due to nonlinear parametric interactions and gives rise to a rapid increase in the noise measure as a function of the generated microwave power. Operating parameters are derived that optimize the power-noise ratio. A long intrinsic response time is found to be beneficial in achieving high power as well as low noise. Other factors affecting the design and choice of material for IMPATT diodes are discussed. An important feature of the presented theory is that a complete design optimization with respect to the power-noise characteristics can be carried out provided reliable information exists about the ionization rates and the drift velocities. A simpler alternative is to obtain the physical quantities governing the power-noise behavior from small-signal admittance and noise measurements. Good agreement has been obtained with experimental power-noise measurements by this method. As an application of this procedure a state of the art comparison is given for GaAs, Ge, and Si diodes at 6 GHz.     

Optimum transit angles of millimeter-wave Si IMPATT diodes

Optimum transit angles for maximum output power in the millimeter-wave IMPATT diodes are calculated analytically by considering the carrier diffusion process through the space-charge region. It is found that the optimum transit angle decreases, as the space-charge layer width reduces. The theoretical results show satisfactory agreement with the previously published experimental results for Si p⁺-n-n⁺abrupt junction diodes.     

Power Amplification with IMPATT Diodes in Stable and Injection-Locked Modes

The behavior of nonlinear power amplifiers using IMPATTdiodes in both stable and injection-locked modes was investigated theoretically and experimentally. A method of graphical interpretation of the characteristics of negative-resistance diode simplifiers, based on the large-signal diode admittance chart, is presented. The characteristics of the simplified model of the reflection-type amplifier using an X-band Read-type IMPATTdiode have been evaluated. The experimental results of power amplification using an X-band Si IMPATTdiode in both stable and injection-locked modes under various circuit conditions are given. It was shown that nonlinearity of the IMPATT diode susceptance causes distortions in the amplification and injection-locking characteristics.     

Noise in IMPATT Diode Amplifiers and Oscillators

The results of experimental and theoretical investigations of the noise characteristics of lMPATT diode amplifiers and oscillators are presented. The oscillator noise is shown to consist of three different contributions: modulation noise, selectively amplified primary noise, and conversion noise. The influence of the active device nonlinearity and load circuit parameters is discussed in detail. The experimental results are in good agreement with the theoretical predictions. It is especially pointed out that the large correlation between AM and FM fluctuations, usually measured in IMPATT oscillators, indicates nonoptimum AM noise performance. Experimental techniques for achieving optimum AM noise performance are demonstrated (orthogonal noise tuning). By a simple extension of the model, the noise behavior of an injection phase-locked oscillator can be described. The calculated AM and FM noise power spectra for the synchronized oscillator are also shown to be in good agreement with experimental results. Finally the signal-to-noise ratio for current modulated IMPATT oscillators is investigated and optimization is demonstrated.     

Power Increase of Pulsed Millimeter-Wave IMPATT Diodes (Short Paper)

The fabrication and encapsulation of single-drift pulsed IMPATT diodes for 73 GHz is described. The transforming properties of the parasitic inductance and capacitance demonstrate the strong influence of diode-mounting technique. The used reduced-height waveguide resonator is described theoretically, giving an indication of optimum matching between resonator and transformed diode impedance. The diodes deliver more than 10-W output power at 73 GHz with 5-percent efficiency, if they are matched to the resonator by proper parasitic.     

Effect of Temperature on Device Admittance of GaAs and Si IMPATT Diodes

The effect of temperature on the small-signal admittance of IMPATT diodes with uniformly doped and high-low doped (Read) structures is investigated experimentafly and theoretically. Small-signal admittance characteristics of X-band Si p+-n-n+, GaAs M-n-n+ (Schottky-uniform), and GaAs M-n+-n-n+ (Schottky-Read) IMPATT diodes are measured at various junction temperatures for different dc current levels. Small-signal analysis is performed on GaAs IMPATT diodes of uniformly doped and high-low doped structures, and the calculated results on temperature dependence of the device admittance are compared with the experimental results. Reasonable agreement is found between theory and experiment. It is shown that GaAs IMPATT diodes are superior to Si diodes in admittance temperature characteristics and that the uniformly doped structure has a small admittance temperature coefficient in magnitude, compared to the high-low doped structure. It is also shown by calculation that the admittance temperature coefficient of a punch-through diode is small in magnitude, compared to that of a non-punch-through diode.     

IMPATT Pump Sideband Noise and its Effect on Parametric Amplifier Noise Temperature

This paper describes an investigation of the amplitude modulation (AM) noise sidebands of silicon IMPATT microwave oscillators and the effect these noise sidebands have on the excess noise temperature of parametric amplifiers. It is shown that the noise temperature may be affected under both large- and small-signal conditions to an extent which depends on the level of pump sideband noise. Simple relationships between easily measurable amplifier properties and pump noise power are given which enable the performance of any combination of pump and amplifier under the two signal conditions to be predicted. A method which simultaneously eliminates the small-signal effect and reduces the large-signal effect to an acceptable level is proposed and demonstrated to be a practical solution.     

X波段硅里德型双漂移崩越二极管外延材料

采用全外延工艺，研制了Ｘ波段里德型双漂移崩越二极管所需πｐｎγＮ￣＋多层外延材料，分析了各过渡区的形成机理及减小其宽度的方法，实现了陡峭的杂质浓度分布。