By Topic

Electron Devices Meeting, 1968 International

Date 23-25 Oct. 1968

Filter Results

Displaying Results 1 - 25 of 141
  • [Front cover and table of contents]

    Page(s): c1
    Save to Project icon | Request Permissions | PDF file iconPDF (1043 KB)  
    Freely Available from IEEE
  • III-V compounds and their applications

    Page(s): 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (84 KB)  

    The III-V compounds and their alloys offer a unique combination of new electrical and optical properties. The available variety of band structure allows these materials to compete for electronic and optical functions not accessible to the elemental semiconductors. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Trends in silicon device technology

    Page(s): 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (84 KB)  

    The present status of silicon device technology is reviewed in order to point out its limitations. The combination of melt-doping, epitaxial growth, and oxide-masked diffusion allows, at least in principle, the construction of about any desired impurity configuration within the silicon crystal. Our present understanding of the silicon-silicon oxide surface allows the design and control of the important surface properties and makes available such important devices as MOS transistors. The limitations of most concern in these areas of wafer fabrication technology are those associated with improving process control and minimizing defects. Effort in this area takes the form of relating cause to effect followed by appropriate detailed process changes. It represents a direction of extreme importance in maximizing the impact of silicon devices through greatly reduced cost. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Reflections on early germanium and silicon single crystal research

    Page(s): 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (85 KB)  

    This talk will recall some of the research on germanium and silicon single crystals in the early days of the transistor. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Electro-optic materials

    Page(s): 14
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (42 KB)  

    The effective use of coherent optical radiation in communications requires low power, wide bandwidth modulators. The most promising modulator materials are those with refractive indices sensitive to electric field. Certain of these materials are also useful in nonlinear optical applications such as optical frequency doublers and optical parametric oscillators. The search for efficient modulator, frequency doubler, and parametric oscillator materials has led to the preparation of a large number of single crystals in the class of oxygen octahedra ferroelectrics. This class includes, for example, lithium niobate, barium sordium niobate and barium titanate. Crystal growth and optical studies have led to nearly optimum electro-optical and nonlinear optical materials within this class. The growth and property control methods that have been used are closely related in many instances to those used in the preparation of single crystal semiconductors. While materials with optimum properties have been found, the requirement for high optical quality crystals that do not optically damage when irradiated with a laser have led to additional material requirements that can be met about which much remains to be understood. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High efficiency operation of IMPATT diodes

    Page(s): 16
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    A new mode of microwave power generation in avalanche diodes, with efficiencies greatly exceeding those obtainable from the IMPATT mode, has recently been discovered. The first experimental observation of these high efficieneies was reported by H. J. Prager, K. K. N. Chang and S. Weisbrod (RCA Laboratories), who observed 60% efficiencies at frequencies below 1 GHz with a silicon diode in pulsed operation. Later R. L. Johnston, D. L. Scharfetter and D. J. Bartelink (BTL) observed 40% efficiency at 3 GHz with a germanium diode also in pulsed operation. Their work in addition gives a theoretical explanation of the observations through detailed computer simulation. Most recently D. E. Iglesias and W. J. Evans (BTL) succeeded in obtaining 40% efficiency in continuous operation with a germanium device at frequencies below 1 GHz. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance and theory of avalanche resonance pumped IMPATT oscillators

    Page(s): 16
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    Avalanche diodes in multiresonant states yielding 20% efficiency at 3 GHz are described and analyzed in this paper. The silicon p+-n-n+punchthrough structure of interest has a nearly abrupt junction and a 95 volt breakdown potential. Optimum transit-time performance at 800amps/cm2is 300 mw with 10% efficiency at 9 GHz in a double-slug coaxial resonator. Under proper RF impedance conditions the operating point will switch to a current density of 2000 amps/cm2. The available power at 9 GHz decreases simultaneously and subharmonic output is observed at 4.5 GHz with 6.5% efficiency. Circuits which provide for separate tuning of the fundamental and harmonic components are utilized to improve this mode. At 3000 amps/cm2, 4 watts with 20% efficiency at 3 GHz is obtained with a third harmonic idler resonance. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Approximate large-signal analysis of IMPATT oscillators

    Page(s): 18
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (120 KB)  

    Considerable insight into the large-signal operating characteristics of IMPATT oscillators has recently been obtained from detailed numerical calculations involving a complete modelling of the physical processes taking place in the diode. However, execution time of existing computer programs is so long that extensive parameter studies are impractical. We present here a parameter study using a technique we have developed for analyzing oscillator modes for which Constant velocity is a good approximation. This technique reduces execution time substantially, but still uses a realistic physical model of the diode. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Determination of germanium ionization coefficients from small signal IMPATT diode characteristics

    Page(s): 18
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (120 KB)  

    Small signal measurements of germanium IMPATT diode admittance in the frequency range from 2 to 8 GHz were taken as a function of current density. These measurements were compared with the small signal admittance calculated using the model developed by Gummel, Scharfetter and Blue. The ionization coefficients and saturated velocities for electrons and holes have been chosen to provide reasonable agreement between theory and experiment for the diode avalanche voltage, zeros of the small signal admittance, and the slope and general shape of the admittance versus frequency curves. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Effect of nonsaturated drift velocity on avalanche-diode performance

    Page(s): 18
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (120 KB)  

    It has become evident from a large-signal analysis of a Read-diode oscillator that in order to obtain high power and efficiency, the r-f voltage swing across the diode becomes comparable to the breakdown voltage and thus the field in the drift region becomes quite low during a part of the r-f cycle. This, of course, results in a nonsaturated or field-dependent velocity in the drift region which essentially changes the drift time and thus affects the power output and efficiency of the device considerably. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bipolar integrated circuits formed in P-type epitaxial layers

    Page(s): 20 - 22
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (200 KB)  

    A new integrated circuit fabrication scheme, using transistors with p-type epitaxially grown base layers was proposed by the authors at the 1968 ISSCC. Transistor-transistor logic gates having a packing density of1.1 times 10^{5}gates/in2have been fabricated using this scheme. The gates have a power × delay of 8 picojoules and a delay of 20 nsec using a 1.5 volt power supply. The output transistors have a peak ftof 2-3.4 GHz. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Self-isolated bipolar transistors in integrated circuits

    Page(s): 20
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    The possibility of implementing bipolar transistors, and hence diodes, in integrated circuits in a self-isolated form has been proposed by one of the authors and independently by B. T. Murphy et al. The present paper is concerned with some of the experimental results of the proposed structures. A p-type epitaxial layer is grown on a p-type substrate where localized n+-layers are buried, and there is no need for additional isolation diffusion besides n+-collector contact diffusion. The higher packing density and the simlicity in processing resulting from the above structures are desirable features for LSI View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Complementary bipolar transistors for monolithic structures

    Page(s): 20
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    A technique is described by which it is now possible to fabricate completely complementary PNP/NPN transistors in a monolithic structure. Until now it has not been possible to make PNP devices with high fTand good hFEin a monolithic structure which are compatible with NPN devices. Both the NPN and PNP transistors have parameters which are identical to those obtained with discrete transistors. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Insulated gate field effect transistor integrated circuits with silicon gates

    Page(s): 22
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (120 KB)  

    The Silicon Gate Technology is a new approach to fabricating insulated gate field effect transistor circuits, in which the metal gate electrode is replaced by a doped, silicon electrode. The work function difference between the gate electrode and semiconductor bulk will now be determined by the doping of the gate electrode. This leads to normally off p-channel devices with threshold voltages typically between 1.1 v and 2.5 v on material with 1000Å gate oxide. It is a self-aligned gate structure and has a buried-gate electrode which allows crossover of gate regions and closer spacing of source-drain contact. The fabrication needs 4 masking steps and was found to be compatible with existing planar technology. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Complementary MOS-bipolar structure

    Page(s): 22 - 24
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (168 KB)  

    Medium and large scale integrated arrays employing complementary MOS transistors, are capable of driving low capacitive loads only. An n-p-n bipolar transistor with an isolated collector is needed when an integrated circuit is required to drive large capacitive loads without deterioration in the maximum operating frequency. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • P+ π P+ MOSFETS: A new approach to complementary integrated circuits

    Page(s): 22
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (106 KB)  

    P-channel enhancement mode MOS field effect transistors have been fabricated on high resistivity P-type (π) silicon substrates. A high off-state impedance can be achieved with zero gate voltage if the substrate resistivity is sufficiently high so that the P+π low-high junctions formed by the diffusion of the drain and source regions exhibit the desired rectifying characteristics. N-channel MOSFETs can also be fabricated on these high resistivity π substrates. While the N-channel devices usually exhibit depletion mode characteristics, both N and P-channel enhancement type MOSFETs can be simultaneously fabricated on a signal substrate if Al2O3-SiO2gate insulating layers are used and if QSSis kept sufficiently small. The channel lengths must be sufficiently large to eliminate SCL current flow from drain to source with zero gate voltage. Off-state leakage currents on the order of nanoamperes have been observed for both units when the channel length was equal to 2 mils. By using techniques such as beam-lead interconnections or dielectric. isolation, complementary MOS integrated circuits can be fabricated on a single substrate and only two diffusions are required. Additional advantages of this approach include: extremely high carrier mobilities, very low threshold voltages for both units and negligible variation of MOSFET charac teristics with reverse substrate bias. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • MOS transistors and integrated circuits with plasma-grown aluminum oxide

    Page(s): 24
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (65 KB)  

    Various studies have been carried out to determine whether SiO2could be replaced by improved insulators in MOS structures and integrated circuits. These studies have been directed toward improving device performance and reducing the requirements for the "ultra clean" technology presently employed. In this paper we report on MOS transistors and integrated circuits fabricated using plasma grown Al2O3. The aluminum oxide is formed by depositing an aluminium film on a fresly cleaned silicon substrate and then anodizing in an oxygen plasma. All other steps in device fabrication use standard silicon technology. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A non-reentrant crossed-field amplifier with cycloiding injected beam

    Page(s): 26
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    Non-reentrant, injected-beam, crossed-field amplifiers usually employ a thin, laminar beam positioned well above the sole electrode. In operation, the beam is gradually bunched by a phase-focusing action. This paper describes the analysis and demonstration of such an amplifier, with one important difference: the electrons of the beam have random, cycloidal trajectories extending to the sole instead of following the usual linear paths. Rapid and effective bunching is accomplished by collecting antiphase electrons on the sole. Experimental results are presented to show that the approach is useful for high current beams. For example, an output power of 600w was obtained at 10 db gain from an 800 ma beam. The advantages and disadvantages of the cycloidal motion are discussed, and the results of computations are given to show the desirable characteristics attainable. For example, an amplifier with a cycloiding beam requires only 35% of the interaction length of a laminar-beam type to produce the same power output, gain, and efficiency. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A high power UHF crossed-field amplifier

    Page(s): 26
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    A forward wave UHF reentrant beam crossed-field amplifier has been developed to deliver 250 kw pulse output over the 406 to 450 MHz range. This amplifier is dc operated and uses a cold secondary emission cathode. Amplification is initiated by the input RF drive pulse and is terminated by a voltage pulse applied to a control electrode, which eliminates the need for a high power pulse modulator. This represents the first application of the dc operating technique to UHF tubes. To adapt the amplifier to forced air cooling its geometry was inverted, with the cathode surrounding the anode. The heat sink for the anode is at the center of the amplifier and cooling air is forced through a simple and compact system of cooling fins. The inverted geometry also provides a significant increase in the available cathode area. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Long pulse, 500 kW, wide band crossed field amplifier

    Page(s): 26 - 28
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (192 KB)  

    This paper describes a tube designed for wide band, long pulse operation at S-band with an output peak power higher than 500 kw and an average power of 5 kw. This tube has a bandwidth of 350 MHz at 1 db, a large signal gain of 17 db, an efficiency of 50% and a signal-to-noise ratio better than 3O db. The main studies are: a water-cooled delay line structure having low dispersion and low spurious electromagnetic radiation; a gun permitting good beam injection and with moderate cathode emission density; a cathode having low barium evaporation; a sole surface having low secondary emission; and a collector having a good distribution of electron beam bombardment. Results are presented on the relationship between signal-to-noise ratio and: heater power, gain, sole secondary emission, beam impedance, and fast mode excitation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Noise, distortion and transmission characteristics of an M-BWO

    Page(s): 28
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    Performance measurements have been made on an experimental FM transmitter using M-BWO. The attractive features of this oscillator are variable power control, high efficiency, wideband modulation capability and light weight. The lack of published data describing the performance of the M-BWO in terms of spectral noise distribution, spurious signals, two-tone third-order distortion, noise power ratio, instantaneous bandwidth and wide bandwidth transmission capabilities has resulted in this investigation. Performance data were obtained with an M-BWO transmitter possessing a residual FM of less than 50 KC. Spurious signals present were found to be greater than --40 db for output powers of 50 watts. Two-tone third-order distortion values varied from 1 to 2% (-37 to --40 db) and noise power ratios measured from --20 to --28 db for an rms frequency deviation of 30 MHz. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A 3.2 millimeter high power magnetron

    Page(s): 28
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    This paper describes a 3.2 mm wavelength, rising sun cavity, pulse magnetron capable of delivering up to 10 kw peak rf power at pulse widths between 5 and 200 nanoseconds at duty cycles up to 0.0002. The reliability of the rising sun design and the high current density Philips' type impregnated cathode ensure relatively long tube life. Modulator design is simplified by the low input capacitance of a rising sun tube in conjunction with the low pulse voltage requirements and relatively high efficiency (8%). This is particularly desirable in the very short nanosecond pulsewidth region needed to fully exploit radar resolution possibilities at this high frequency. Development of the 3.2-mm magnetron was based on experience obtained in the development of a family of existing millimeter magnetrons, in particular, the 4-mm and the 2.5-mm tubes. This paper describes the anode and the hobbing method used for making it. Also described is the cathode and procedures by which it is aligned in the anode: optically during assembly, and electrically after evacuating the tube. Electrical test procedures and the results are described for both cold and hot tests, including descriptions of specialized WR10 waveguide equipment designed for use in evaluating these tubes. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Studies of crossed field amplifiers relating to stability, noise and electron guns

    Page(s): 28
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB)  

    This paper is presented in two parts: A.) Considerations of Stability and Noise Improvement of Crossed Field Amplifiers, and B.) Beam Analyzer Measurements of a Wide Dynamic Range Crossed Field Gun. A.) The authors have confirmed that in the absence of drive signal, oscillation instabilities in high power crossed field amplifiers are a forward wave phenomenon. Analyses suggest that these instabilities are caused by cyclotron wave interaction. Predicted frequencies and/their tuning are in fair agreement with measurements. Practical designs are discussed in relation to stability, efficiency and electron gun design. B.) The authors have proposed a crossed field gun for optimum beam launching under a wide range of cathode current densities in a fixed magnetic field. Desirable frequency and amplitude modulation characteristics of the device output are expected, using this gun. A beam analyzer is being assembled comprising the Wide Dynamic Range Gun, a drift region and collector. Grid wires in the drift region will permit study of the nature of the electron beam. The design is being simulated on a digital computer, including space charge effects. The computer model will be briefly discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Increased rate of rise of voltage on high power cathode pulsed crossed field devices

    Page(s): 30
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (78 KB)  

    This paper discusses the maximum rate of rise of voltage (RRV) which can be applied to the cathode of a crossed field device. Recent developments in high peak power, narrow pulse width transmitters have indicated that the established criteria for RRV are not completely valid. Experience has shown that the RRV specified by crossed field tube designers is not a limitation inherent in the devices themselves but rather a function of the matching of the pulser to the tube. Attempts to achieve narrow pulse widths from magnetrons with conventional line type pulsers have tended to confirm the specified maximum RRV. However, when a Darlington or a Blumlein pulse forming network is used in place of the conventional network and pulse transformer, RRV's two to three times higher than the maximum specified have been successfully applied with stable operation. The results indicate that RRV is relatively unimportant as long as overshoot of the modulator pulse is avoided. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The spin magnetron, a simple and compact solution to broad-band frequency-agility radar

    Page(s): 30
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (78 KB)  

    This paper describes the construction and principle of operation of spin-tuned magnetrons, such as they have been developed at Philips, based on patented ideas. Emphasis has been put on high-power magnetrons for X- and Ku-band radars. Magnetron data for these frequency bands are presented together with calculated data for lower frequency bands. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.