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IBM Journal of Research and Development

Issue 5 • Date Sept. 1967

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Displaying Results 1 - 15 of 15
  • Reverberation Chamber Determination of the Acoustic Power of Pure-Tone Sources

    Publication Year: 1967 , Page(s): 492 - 501
    Cited by:  Patents (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (558 KB)  

    A method was developed that is used to determine the acoustic power radiated by pure-tone and “nearly-pure-tone” sources in a reverberation chamber. The 3-dimensional standing wave sound field generated by a pure-tone source is sampled by a microphone that slowly sweeps a circular path in the chamber. The method relates the average value of the sound pressure at the peaks of the “sample” to its effective rms pressure. The acoustic power of the source is then readily calculated from the effective rms pressure, the volume of the chamber and its absorption. View full abstract»

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  • The Electron Beam Scanlaser: Theoretical and Operational Studies

    Publication Year: 1967 , Page(s): 502 - 510
    Cited by:  Papers (5)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (507 KB)  

    This paper presents the theory, design, and initially observed operating parameters of the Electron Beam Scanlaser, a scanning laser device in which a modified electro-optic display tube selects one of many degenerate transverse modes of a flat-field conjugate resonator. The version considered uses a KDP crystal in the mode selector and an ionized mercury hollow cathode discharge as active element. Some observations reported are resolution (10 lines/mm); sweep rate (100 µsec/line); light decay time (2 msec, minimum); and power/spot (1 W pulsed). Laser output power is about 30 dB greater than electron beam power. View full abstract»

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  • Multiple-Curie-Point Capacitor Dielectrics

    Publication Year: 1967 , Page(s): 511 - 519
    Cited by:  Papers (2)  |  Patents (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (594 KB)  

    This paper reports an experimental study of the preparation of screened printed dielectric materials having high dielectric constants and a controlled temperature characteristic. The technique uses mixtures of sintered bodies which have different Curie points and which retain their identity after processing. Barium-strontium and barium-lead titanate mixtures have been prepared having a dielectric constant of about 500. This process has been used to produce negative-positive-zero, negative, and positive thermal coefficient bodies over various temperature ranges. View full abstract»

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  • Two Interconnection Techniques for Large-Scale Circuit Integration

    Publication Year: 1967 , Page(s): 520 - 526
    Cited by:  Papers (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (520 KB)  

    Studies of the feasibility of custom-interconnected, large-scale integrated circuits required the development of means for converting computer-generated wiring instructions into metallic conductors on a semiconductor wafer. The resulting equipment took two forms. In one, ultraviolet light serves to expose photoresists on a mechanically translated wafer; the other employs an electron beam. Both systems were adequate to produce two-mil-wide conductors, but differ in their potential for achieving high production rates or very thin lines. View full abstract»

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  • Estimation of Temperature Rise in Electron Beam Heating of Thin Films

    Publication Year: 1967 , Page(s): 527 - 536
    Cited by:  Papers (3)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (525 KB)  

    Expressions are given for estimating the transient temperature distribution in a thin film heated by an electron beam. Graphical presentations in terms of dimensionless (reduced) variables are included to aid in specific calculations for designing an electron beam for use as a heating tool. View full abstract»

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  • A Numerical Integration Technique for Ordinary Differential Equations with Widely Separated Eigenvalues

    Publication Year: 1967 , Page(s): 537 - 543
    Cited by:  Papers (3)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (422 KB)  

    An explicit nonlinear numerical integration method is presented for the solution of certain large systems of ordinary differential equations in which there is a large spread of time constants, the smallest one being real. The integration formulas are derived and some local truncation error data given for small step sizes. Some applications are discussed where the new technique saves considerable computation time over classical methods. View full abstract»

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  • Power Conversion in Nonlinear Resistive Elements Related to Interference Phenomena

    Publication Year: 1967 , Page(s): 544 - 552
    Cited by:  Papers (2)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (487 KB)  

    This paper derives the power conversion in a nonlinear resistive element that is in series with linear resistors. The derivation of the power conversion is analogous to the Manley and Rowe analysis. The power at the fundamental and intermodulation frequencies is defined as the product of the Fourier coefficients of the current and voltage components at these frequencies. In the analysis, the Fourier coefficients are derived as functions of the generator voltage in a lumped-element circuit. To evaluate the Fourier coefficients, the relationship between current and generator voltage is expressed by a power series. The coefficients of the power series are given in the form of polynomials that are valid for nonlinear resistive elements with exponential characteristics. For the investigation of interference phenomena, the equivalence between the lumped-element circuit and a microwave circuit is derived and the generator voltage is related to the power flux density carried by the incident waves intercepted by support structures. The transfer of power at the intermodulation frequencies to radiating structures is then described. Finally, the power at the intermodulation frequencies is evaluated numerically for different power levels in the incident waves. The computed values were verified experimentally. View full abstract»

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  • On the Equation i = i0 [exp α (v − Ri) − 1]

    Publication Year: 1967 , Page(s): 553 - 554
    Cited by:  Papers (2)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (253 KB)  

    In general, the current-voltage characteristic of a nonlinear resistive element can be represented by an exponential function: i = i0(eαe − 1), where i is the current through the nonlinear resistor, e is the voltage across the resistor, and i0 and α are constants. In a circuit containing a linear resistor R in series with the nonlinear resistor, the characteristic becomes i = i0[eα(v−R i)− 1], where v is a series voltage source. View full abstract»

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  • Domain Wall Energy Measurements using Narrow Permalloy Strips

    Publication Year: 1967 , Page(s): 555 - 557
    Cited by:  Papers (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (293 KB)  

    Middelhoek1 proposed in 1961 that the domain structure of narrow thin film strips could be used to measure energies of domain walls and Kuwahara et al. have likewise suggested this method.2 When measurements were attempted by these authors it was found that experimental results of wall energy were about a factor of four lower than calculated values. Furthermore, and contrary to theoretical calculations, there was no variation of wall energy density with film thicknes.2 This note proposes improvements in the experimental procedure, and reportss ome results which resolve the inconsistencies in the literature. View full abstract»

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  • Propagation of Signals in Nonlinear Transmission Lines

    Publication Year: 1967 , Page(s): 558 - 562
    Cited by:  Papers (5)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (392 KB)  

    This communication reports the results of a theoretical investigation of the propagation of signals in transmission lines whose nonlinear parameters are distributed capacitance and conductance. Such lines have their physical counterpart in lossless transmission lines that are loaded with closely spaced transistor bases or junction diodes, and in waveguides filled with certain ferroelectric ceramic materials. The analysis is carried out by conventional perturbation theory, and therefore the nonlinearities and dissipation are necessarily assumed to be small. The conditions for the formation of shock waves in such lines are also derived. View full abstract»

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  • On the Magnetic Properties of Sputtered NiFe Films

    Publication Year: 1967 , Page(s): 563 - 569
    Cited by:  Papers (2)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (482 KB)  

    Reproducibility and control of magnetic properties have been significant problems in the preparation of Permalloy films by cathodic sputtering. The data presented in this paper illustrate the reduced sensitivity to gaseous impurities that can be achieved by applying a suitable negative bias to an 81% Ni-19% Fe Permalloy film that is being deposited by dc sputtering. Results are shown which compare the magnetic properties as a function of deposition rate achieved with and without a bias potential applied to the film during deposition. Data are also presented showing the effect of film bias on magnetic properties when known concentrations of oxygen and nitrogen are present in the atmosphere during deposition. The evidence shows that the effect of the bias is to reduce the quantity of system atmosphere impurity included in the film. The bias technique has permitted, with good reproducibility, accurate experimental determination of the effect of such control parameters as substrate temperature on magnetic properties. (Wall motion threshold H0, anisotropy field Hk0, and dispersion α90 are plotted as a function of substrate temperature.) In addition, data are shown which demonstrate the compositional control and simplicity of film thickness and deposition rate control which are inherent in the sputtering process. View full abstract»

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  • Technical Papers by IBM Authors Published Recently in Other Journal

    Publication Year: 1967 , Page(s): 570 - 578
    Save to Project icon | PDF file iconPDF (701 KB)  
    Freely Available from IEEE
  • Patents Recently Issued to IBM Inventors

    Publication Year: 1967 , Page(s): 579 - 580
    Save to Project icon | PDF file iconPDF (262 KB)  
    Freely Available from IEEE
  • Authors

    Publication Year: 1967 , Page(s): 581 - 582
    Save to Project icon | PDF file iconPDF (303 KB)  
    Freely Available from IEEE
  • Contents of previous issue

    Publication Year: 1967 , Page(s): 583
    Save to Project icon | PDF file iconPDF (171 KB)  
    Freely Available from IEEE

Aims & Scope

The IBM Journal of Research and Development is a peer-reviewed technical journal, published bimonthly, which features the work of authors in the science, technology and engineering of information systems.

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Editor-in-Chief
Clifford A. Pickover
IBM T. J. Watson Research Center