Showing papers on "IMPATT diode published in 1978"
TL;DR: In this article, analytical models of dc and small-signal characteristics for Read-type diode structures are given which incorporate both tunneling and avalanche mechanisms, and a "dead-space" analysis is shown to be fundamental to accurate models of thin generation regions.
Abstract: Analytical models of dc and small-signal characteristics for Read-type diode structures are given which incorporate both tunneling and avalanche mechanisms. A "dead-space" analysis is shown to be fundamental to accurate models of thin generation regions. Pure tunneling and pure avalanche appear as the two limiting cases of the general models. In the pure tunneling limit, the diode oscillator will operate in the tunnel transit-time (TUNNETT) mode. The TUNNETT oscillator would be attractive for low-noise and medium power and efficiency applications. For diode structures which operate between the pure TUNNETT and IMPATT modes, there exists a noise performance-output power tradeoff. Computer solutions of the analytical models, for specific diode structures and operating conditions, are given, and the results are discussed and compared with experimental results whenever possible.
46 citations
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TL;DR: In this paper, the fundamental oscillation at frequencies from about 100 up to 248 GHz has been obtained from the pulse-driven p+-n-n+ diodes.
Abstract: The tunnel-injection-transit-time (TUNNETT) diode is operated at a high frequency and has a low-noise level compared to the IMPATT diode. The tunnel injection in a thin carrier generating region of the TUNNETT depends strongly on the electric-field intensity over 1000 kV/cm where the ionization of carriers can be neglected, leading to a higher efficiency performance than that of the IMPATT. GaAs TUNNETT diodes with p+-n and p+-n-n+ structures have been fabricated by a new LPE method (the temperature-difference method under controlled vapor pressure). The fundamental oscillation at frequencies from about 100 up to 248 GHz has been obtained from the pulse-driven p+-n-n+ diodes. This paper describes the details of the oscillation characteristics of GaAs TUNNETT diodes.
46 citations
TL;DR: In this article, a method for locking impatt oscillators by illuminating the impatt diode with a low-power laser beam, amplitude modulated at microwave frequency, is described.
Abstract: A method for locking impatt oscillators by illuminating the impatt diode with a low-power laser beam, amplitude modulated at microwave frequency, is described. A large-signal theory of impatt operation, including the effects of finite reverse saturation currents and their modulation by the laser beam, is presented and predicts locking ranges of several tens of MHz with laser powers of a few mW
28 citations
01 Jan 1978
TL;DR: In this paper, a method of locking IMPATT oscillators by illuminating the IMPATT diode with a low-power laser beam, amplitude modulated at microwave frequency, is described, and the effect of reverse saturation current modulation by the laser beam is presented and predictions of locking ranges obtainable are made.
Abstract: A method of locking IMPATT oscillators by illuminating the IMPATT diode with a low-power laser beam, amplitude modulated at microwave frequency, is described. A large-signal theory of IMPATT operation which includes the effect of reverse saturation current modulation by the laser beam is presented and predictions of locking ranges obtainable are made. The analytic theory is supplemented by a large-signal computer simulation of an IMPATT oscillator under microwave-modulated illumination. Finally experiments under way at present to test these predictions are described.
27 citations
TL;DR: In this paper, the performance of avalanche diode structures with an etched optical window at the top contact has been evaluated and it was shown that the optical window does not introduce appreciable series resistance nor degrade oscillator performance.
Abstract: The r.f. performance of avalanche diode structures with an etched optical window at the top contact has been evaluated. Diode Q and r.f. oscillator tests in X -band IMPATT and S -band TRAPATT silicon diodes show that the optical window does not introduce appreciable series resistance nor degrade oscillator performance.
22 citations
TL;DR: An improved nonlinear circuit model for IMPATT diodes is presented for which each element bears a simple relationship with the physical operating mechanisms inside the device.
Abstract: An improved nonlinear circuit model for IMPATT diodes is presented for which each element bears a simple relationship with the physical operating mechanisms inside the device. The model contains lumped nonlinear elements as well as lumped and distributed linear elements. In its most general form it incorporates various second-order effects heretofore neglected in other circuit models. These include the effects due to unequal hole and electron ionization rates, unequal hole and electron drift velocities, and carrier diffusion.
21 citations
Book•
01 Jan 1978
TL;DR: The avalanche diode as mentioned in this paper is a semi-conductor diode that is designed to operate at high current densities and is specially constructed to prevent overheating even for pulsed operation.
Abstract: 1,241,555. Semi-conductor devices. NATIONAL RESEARCH DEVELOPMENT CORP. 27 Nov., 1968 [28 Nov., 1967], No. 54012/67. Heading H1K. [Also in Division H3] An avalanche diode oscillator has the diode junction formed by ion implantation, the implanted layer having discrete regions 2 of deeper ion implantation extending into the active region so that the avalanche breakdown is confined to those regions to produce high current density. The avalanche diode is designed to operate at high current densities. The diodes are specially constructed to prevent overheating even for pulsed operation. A P + N N + diode may have an ion implanted P + layer 1 with discrete regions 2 of deeper ion implantation produced by concentrating the ion implantation beam at these regions and increasing the energy of the beam. The active region of the diode is an epitaxial N-type layer 3. The diode has metallic contacts 5, 6 alloyed to the P+ layer 1 and an N+ substrate 4. When a reverse voltage is applied to the P + N junction and when avalanche breakdown occurs the electric field is concentrated between the regions 2 and the substrate 4. The material between the regions 2 acts as a heat sink.
17 citations
TL;DR: In this paper, it is shown that the TEM parallel-plate waveguide mode of the junction is modified by the injection of electrons at the p+n junction (or Schottky contact).
Abstract: The small-signal analysis of a distributed IMPATT diode ifdicates the existence of a traveling-wave mode. The severe power-frequency limitation as well as the associated low impedance level of the discrete diode appear avoidable. No external resonant circuitry is needed. It is shown that the TEM parallel-plate waveguide mode of the junction is modified by the injection of electrons at the p+ -n junction (or Schottky contact). The transverse electric field takes on a traveling-wave nature in the transverse direction tracking the injected electrons, and a small longitudinal electric field will also be present. In previous papers on IMPATT traveling-wave structures, the IMPATT effect was lumped into an effective complex permittivity in a composite layer model or into an effective shunt admittance in a transmission line model. The current work attempts to incorporate the IMPATT mechanism into the wave model and considers the actual carrier field interaction. The srnall-signal analysis yields an analytic field solution and a characteristic equation for the complex propagation constant. Solutions are found and documented for various frequencies and bias current densities. For the particular structure considered, at 12 GHz with a bias current density of 1000 A/cm/sup 2/ a gain of 72 dB/cm was found.
17 citations
TL;DR: In this article, a theory of mode locking in the microwave regime is presented and the use of solid-state microwave devices for this application is described, using an IMPATT diode as the gain element and a Schottky barrier diode in the role of a saturable absorber.
Abstract: A theory of mode locking in the microwave regime is presented. The use of solid-state microwave devices for this application is described. A system that has been built using an IMPATT diode as the gain element and a Schottky barrier diode in the role of a saturable absorber is analyzed. Passive, combined passive, and forced mode locking have been demonstrated experimentally. The system had a round-trip time of 25 or 50 ns. Pulse lengths between 4 and 15 ns were observed. Self-starting and stability requirements are investigated.
11 citations
TL;DR: In this article, a process that combines ion-implantation doping with planar and mesa-etching techniques was developed for the fabrication of fully passivated millimeter-wave IMPATT diodes.
Abstract: A process has been developed that combines ion-implantation doping with planar and mesa-etching techniques for the fabrication of fully passivated millimeter-wave IMPATT diodes. The device geometry consists of an IMPATT diode surrounded by a two-layer annular region of passivation: one layer of high-resistivity semiconductor and the other of thick insulator material. Devices constructed with this new geometry have sufficient mechanical strength to allow direct mounting into microwave circuits without the use of an insulator standoff and metal ribbon package arrangement. A simple model of the diode-circuit interaction is used to estimate the degradation in microwave performance as a function of the passivation parasitics. These results are compared to a diode with no parasitic losses. Based on the I2-PLASA process, a fully passivated silicon IMPATT diode was fabricated for V-band (50-75-GHz) operation. Degradation factors of approximately 50 percent are predicted for the present devices. A continuous-wave output power of 100 mW was obtained at 62 GHz from an I2-PLASA IMPATT diode with an implanted p+-n-n+doping profile. Mechanical tuning characteristics of these devices were found to be more broad-band than standard packaged diodes. The measured AM and FM noise spectra close to the carrier were representative of standard single-drift silicon millimeter-wave IMPATT diodes.
10 citations
01 Jan 1978
TL;DR: In this article, a theory of mode locking in the microwave regime is presented and the use of solid-state microwave devices for this application is described, and a system that has been built using an IMPATT diode as the gain element and a Schottky barrier diode in the role of a saturable absorber is analyzed.
Abstract: Abstwzct—A theory of mode locking in the microwave regime is presented. The use of solid-state microwave devices for this application is described. A system that has been built using an IMPATT diode as the gain element and a Schottky barrier diode in the role of a saturable absorber is analyzed. Passive, combined passive, and forced mode locking have been demonstrated experimentally. The system had a round-trip time of 25 or 50 ns. Pulse lengths between 4 and 15 ns were observed. Self-starting and stability requirements are investigated.
TL;DR: In this article, a large-signal analysis of a double-drift silicon IMPATT diode at 50 GHz was performed and it was shown that the device is capable of output power of 1.1 W and efficiency of 20 percent for a device area of 2 × 10-5 cm2 at a dc biasing current density of 12 kA/cm2 and ac voltage amplitude of 12 V.
Abstract: Large-signal analysis of a lo-hi-lo double-drift silicon IMPATT diode at 50 GHz shows that the device is capable of output power of 1.1 W and efficiency of 20 percent for a device area of 2 × 10-5cm2at a dc biasing current density of 12 kA/cm2and ac voltage amplitude of 12 V. It is also found that, both output power values and efficiencies decrease with increasing enhanced leakage current.
27 Jun 1978
TL;DR: In this paper, a tunnett diode with p+n and p+nn+ structure has been fabricated by a new LPE method (TDM under CVP).
Abstract: The Tunnel injection transit time (Tunnett) diode operates in higher frequency region and with lower noise level than that of the Impatt diode. In thin carrier generating region, the tunnel injection which depends steeply on the electric field intensity over 1000 kV/cm, where the ionization of carriers can be neglected, leads to the higher efficiency operation of the Tunnett than that of the Impatt. GaAs Tunnett diodes with p+n and p+nn+ structure have been fabricated by a new LPE method (TDM under CVP). The fundamental oscillation at the frequency from about 100 GHz up to 248 GHz has been obtained from the p+nn+ diode.
TL;DR: In this paper, the effect of the carrier dispersion caused by avalanching on the small signal admittance and the transient step response in the avalanche region of an idealized IMPATT diode having a uniform electric field profile was analyzed.
Abstract: Numerical analysis has been performed on the effect of the carrier dispersion caused by avalanching on the small signal admittance and the transient step response in the avalanche region of an idealized IMPATT diode having a uniform electric field profile. The degree of dispersion, referred to hereafter as Avalanche Induced Dispersion (AID), depends on the relative magnitudes of ionization rates of the two carriers. AID becomes largest when the two ionization rates are equal and decreases with increasing discrepancy between them. It is found that the build-up of an avalanche can be faster if either electrons or holes are strongly ionizing than when both of them ionize equally. Also, the small signal negative conductance is minimum when the dispersion is most pronounced. Since the time delay in the avalanche build-up depends strongly on AID, the upper limit of the high-frequency performance of IMPATT diodes can be estimated from the theoretical value of AID.
01 Jan 1978
TL;DR: In this article, the effect of optically generated carriers on the dynamics of an IMPATT diode oscillator was investigated over a wide range of operating conditions and optical power level.
Abstract: The results of detailed computer simulations of the effect of optically generated carriers on the dynamics of an IMPATT diode oscillator are presented. Both small- and large-amplitude oscillations are examined over wide ranges in operating conditions and optical power level. Agreement is obtained between the theoretical results and experimental observations. Key results of the calculations are used to establish the extent to which the amplitude and frequency of a conventional IMPATT oscillator can be optically modulated as well as the operating conditions under which this control is optimized.
TL;DR: In this article, the gallium arsenide Read IMPATT diodes for K a -band (36-38 GHz) operation were designed and fabricated for manufacturability and high yield.
Abstract: We have designed, fabricated, and evaluated gallium arsenide Read IMPATT diodes for K a -band (36-38 GHz)operation. The devices were packaged units intended for manufacturability and high yield. Oscillator output power as high as 710-mW CW was obtained at 9-percent efficiency. This paper describes design and fabrication techniques employed and discusses the potential and limitations of such devices.
TL;DR: In this article, a new operation mode, the "surfing mode", is proposed as an explanation for the high efficiency operation of high-low-type GaAs IMPATT diodes.
Abstract: A new operation mode, the "surfing mode," is proposed as an explanation for the high-efficiency operation of high-low-type GaAs IMPATT diodes. This mode is characterized by the concept that the avalanche charge pulse drifts synchronously with the movement of the front edge of the depletion layer at a velocity higher than the saturation velocity. The design chart of high-low-type GaAs IMPATT diodes is determined on the basis of the concept of the "surfing mode." The high-low-type GaAs IMPATT diodes designed using this chart exhibited output powers of 15.3 W ( \Delta T_{j} = 210°C) at 6.1 GHz with 25-percent efficiency.
01 Jan 1978
TL;DR: In this paper, a five-stage high-power IMPATT diode amplifier (1μs pulsewidth, 25% duty cycle) has been developed using resonant cavity power combiners for the final three stages.
Abstract: A five-stage high-power IMPATT diode amplifier(1μs pulsewidth, 25% duty cycle) has been developed using resonant cavity power combiners for the final three stages. Progress will be reported towards a goal of 1kW output at 10GHz.
TL;DR: In this paper, a GaAs single-drift Schottky-barrier Impatt diodes mounted in a full-height IEC-R740 waveguide (3.1 × 1.55 mm2) have been observed between 60 and 96 GHz in pulsed operation.
Abstract: Oscillation of GaAs single-drift Schottky-barrier Impatt diodes mounted in a full-height IEC-R740 waveguide (3.1 × 1.55 mm2) has been observed between 60 and 96 GHz in pulsed operation. By bias-current tuning, a range of up to 19 GHz was covered with a single diode.
Patent•
23 Aug 1978TL;DR: In this article, an avalanche diode for radiation detection with very low noise by using a structure having four successive layers (4,3,2.1) of the same conductivity type with alternately high and low doping is presented.
Abstract: An avalanche diode for radiation detection with very low noise by using a structure having four successive layers (4,3,2.1) of the same conductivity type with alternately high and low doping. Particularly suitable as a planar photo- avalanche diode.
Patent•
28 Nov 1978
TL;DR: In this paper, a fabrication process for a large number of mesa diodes with a radial waveguide integral with the structure, forming a "easy to handle" unit is described.
Abstract: A structure consisting of a semiconductive device e.g. an IMPATT diode destined to transmit high frequency electromagnetic waves through a radial waveguide integral with the structure, forming a "easy to handle" unit. A fabrication process allowing a large number of units to be made utilizing batch processing techniques, is provided. The process includes forming a plurality of mesa diodes on a semiconductor wafer, coating the wafer with a first insulating layer (filling the intervals between the mesa tables), then depositing on the wafer a plate of a solid dielectric with openings for access to the upper part of diodes. The diodes are spaced enough to allow forming around each of them a radial waveguide using a portion of the solid dielectric for propagation medium and for walls, on one hand a metallization extending the biassing electrodes of the upper parts of diode, and on the other hand, a metallic base supporting the assembly after grinding of the substrate of the wafer. The diameter of the radial waveguide is of the order of one wavelength, measured in the solid medium.
TL;DR: In this paper, a computer program which includes both electronic and thermal processes has been used to study avalanche oscillations in a diode which is punched through only well above breakdown, and the frequency of the IMPATT oscillations was found to vary with the square root of the current over a factor of 100 in current.
Abstract: A computer program which includes both electronic and thermal processes has been used to study avalanche oscillations in a diode which is punched through only well above breakdown. IMPATT, relaxing avalanche, and MULTIPATT oscillations have been studied. The MULTIPATT mode is shown to be a superpesition of transit-time oscillations upon a relaxation oscillation. It is postulated that the TRAPATT mode is initiated by the IMPATI mode via the MULTIPATI mode. The frequency of the IMPATT oscillations was found to vary with the square root of the current over a factor of 100 in current. For parallel operation of TRAPATT diodes, it is shown that nonpunched-through diodes should be used.
01 Oct 1978
TL;DR: In this paper, a tunnett diode with p+n and p+ nn+ structures has been fabricated by a new LPE method (TDM under CVP), and an output power of about I mW has also been obtained at 200 GHz.
Abstract: The tunnel injection increases steeply by the electric field intensity over 1000 kV/cm and the thickness of the tunnel injection region less than 100 A is suitable for the injection responsible above short millimeter wave where the impact ionization ceases to follow, because of the larger time constant. [3] The Tunnel injection transit time (Tunnett) diode operates in higher frequency region with lower noise level than those of the Impatt diode. Tunnett diode will be useful in higher frequency in the range from 100 to 1000 GHz over the range for GaAs SIT. GaAs Tunnett diodes with p+n and p+ nn+ structures have been fabricated by a new LPE method (TDM under CVP). Oscillation in the circuit from 75 to 325 GHz have been examined and the pulsed fundamental oscillation up to 278 GHz has been obtained from the p+nn+ diode. An output power of about I mW has also been obtained at 200 GHz.
27 Jun 1978
TL;DR: A 490 mW circulator-coupled IMPATT reflection amplifier with 6.9 dB gain at 59.25 GHz and 1.9 GHz bandwidth for 1 dB rolloff has been developed using double-drift IMPATT diodes on diamond in a novel circuit designed to minimize subharmonic instabilities.
Abstract: A 490 mW circulator-coupled IMPATT reflection amplifier with 6.9 dB gain at 59.25 GHz and 1.9 GHz bandwidth for 1 dB rolloff has been developed using double-drift IMPATT diodes on diamond in a novel circuit designed to minimize subharmonic instabilities.
Patent•
16 Jun 1978
TL;DR: In this article, an avalanche diode of gallium arsenide has been used to optimize the coefficient of ionization by impact in the case of impacts initiated by holes when the electrical field propels the carriers along the axis of 1 1 1 of the monocrystal.
Abstract: In an avalanche diode of gallium arsenide, e.g. an IMPATT diode, the optimization of the coefficient of ionization by impact in the case of impacts initiated by holes when the electrical field propels the carriers along the axis of 1 1 1 of the monocrystal, has been utilized. The structure comprises a substrate of Ga As with two large faces perpendicular to the axis 1 1 1 and layers obtained by epitaxial growth from one of these large faces. Arrangements are made to ensure that the electrical field is as parallel as possible to this crystalline axis. The improvement in efficiency is of the order of 20%.
01 Oct 1978
TL;DR: In this paper, two identical MIC-transmit-receive units wlih 1 W CW output each were forming a twin module, which produced phase tracking of about 0.8 phase degrees/°C in CW operation, thereby setting limits for uncontrolled temperature differences in larger arrays.
Abstract: Two identical MIC-transmit-receive units wlih 1 W CW output each were. forming a twin module. GaAs IMPATT diode power amplifiers and ferrite phase shifters were used. This type of components produced phase tracking of about 0.8 phase degrees/°C in CW operation, thereby setting limits for uncontrolled temperature differences in larger arrays. With 3 m us pulses, an intra-pulse phase variation of less tan 10 degrees was measured. Improvements concerning phase stability and efficiency are expected by the use of GaAs FETs and temperature compesated ferrites or replacement of ferrites by nonferrite components.
27 Jun 1978
TL;DR: In this article, the spectral purity of the fundamental mode and overmoded resonant cavity IMPATT diode power combiners operating as stable reflection amplifiers was measured and was found to be satisfactory for use in sophisticated RADAR systems.
Abstract: The characteristics of fundamental mode and overmoded resonant cavity IMPATT diode power combiners operating as stable reflection amplifiers are described. The spectral purity of this class of RF amplifier has been measured and was found to be satisfactory for use in sophisticated RADAR systems.
TL;DR: In this paper, the intermodulation products generated in an actively compensated X-band IMPATT amplifier have been measured and compared with the corresponding uncompensated amplifier, and the 3rd-order intercept point increases from 11.5 dB to 23 dB.
Abstract: The intermodulation products generated in an actively compensated X-band IMPATT amplifier have been measured and compared with the corresponding uncompensated amplifier. The 3rd-order intercept point increases from 11.5 dB to 23 dB, giving an improvement of 11.5 dB.
Patent•
07 Sep 1978
TL;DR: In this paper, a negative impedance device, e.g. a Gunn or IMPATT diode, is used to produce continuous or pulsed millimeter waves of e. g. 35 GHz.
Abstract: The microwave oscillator has a negative impedance device, e.g. a Gunn or IMPATT diode. The diode is located in a cavity resonator and produces continuous or pulsed millimeter waves of e.g. 35 GHz. The diode (4) is located in the centre of a normal section of waveguide acting as a cavity resonator. There is a filter resonator (2) which prevents power passing out via the DC supply line of the diode. An impedance transformer (3) is located on the opposite side to the diode earth connection to match the diode to the cavity resonator.