Applications of advanced materials technologies to vacuum electronic devices

The applications of advanced engineering materials in modern vacuum electronic devices are reviewed. Unique materials with desirable thermal, mechanical, electrical, and magnetic properties are playing a crucial role in raising the average power capability, bandwidth, and efficiency of microwave and millimeter wave amplifiers and oscillators. Five major materials-related topics and technologies are covered in this article: diamond electromagnetic windows and electrode supports; electromagnetically lossy composite ceramics for control of instabilities; methods of cooling metal structures; pyrolytic graphite beam collectors and electron-gun modulation grids; and rare-earth permanent magnets for confining electron beams. For each topic, this article reviews the background physics. describes the importance of the technology to vacuum electronics, presents illustrative examples of how such technologies perform, and reviews current results from the literature.

[1]  J. T. Mark,et al.  New high efficiency 500 kW tetrodes for short wave broadcast , 1988 .

[2]  S. Morgan,et al.  Helix waveguide , 1956 .

[3]  W. Lawson,et al.  A modified method for producing carbon-loaded vacuum-compatible microwave absorbers from a porous ceramic , 1991 .

[4]  P. Ramins,et al.  Improvements in MDC and TWT overall efficiency through the application of carbon electrode surfaces , 1986, IEEE Transactions on Electron Devices.

[5]  J. Clarke,et al.  Shaping of cylindrically symmetric magnetic fields with permanent magnets , 1986 .

[6]  H. Leupold,et al.  Permanent magnets for magnetic resonance imaging , 1986 .

[7]  H. A. Leupold,et al.  Multi‐Tesla permanent magnet field sources , 1993 .

[8]  E. Zaidman,et al.  Emission gated device issues , 1991 .

[9]  Ii E. Shobert.  Carbon, Graphite, and Contacts , 1976 .

[10]  A. V. Gaponov-Grekhov,et al.  Applications of High-Power Microwaves , 1994 .

[11]  W. Lawson,et al.  A 30-MW Gyroklystron-Amplifier Design for High-Energy Linear Accelerators , 1985, IEEE Transactions on Plasma Science.

[12]  J. M. McDonald,et al.  Test results from a pumped single-phase porous metal heat exchanger , 1993, Optics & Photonics.

[13]  O. Sauseng,et al.  Thermal properties and power capability of helix structures for millimeter waves , 1978, 1978 International Electron Devices Meeting.

[14]  M. J. Wheeler.  Heat and Mass Transfer , 1968, Nature.

[15]  W. J. Choyke,et al.  Physical Properties of SiC , 1997 .

[16]  R. Collin.  Foundations for microwave engineering , 1966 .

[17]  Erle I. Shobert,et al.  CARBON AND GRAPHITE , 1964 .

[18]  H. Seifert,et al.  Rocket Propulsion Elements , 1963 .

[19]  H.G. Kosmahl,et al.  Modern multistage depressed collectors—A review , 1982, Proceedings of the IEEE.

[20]  Terrence W. Simon,et al.  Flow boiling critical heat flux on small heated regions , 1993, Optics & Photonics.

[21]  R. N. Tamashiro,et al.  60 percent efficient K-band TWT using a new diamond rod technology , 1989, International Technical Digest on Electron Devices Meeting.

[22]  H. A. Leupold,et al.  A Permanent Magnet Circuit Design Primer. , 1996 .

[23]  Y. Takita,et al.  A forced gas-cooled single-disk window using silicon nitride composite for high power CW millimeter waves , 1997 .

[25]  R. Parker.  Advances in Permanent Magnetism , 1990 .

[26]  Joseph Alison King.  Materials handbook for hybrid microelectronics , 1988 .

[27]  A. Curren,et al.  Electron reflection and secondary emission characteristics of sputter-textured pyrolytic graphite surfaces , 1981 .

[28]  A. Curren,et al.  Carbon and carbon-coated electrodes for multistage depressed collectors for electron-beam devices—A technology review , 1986, IEEE Transactions on Electron Devices.

[29]  Thomas F. Fleming,et al.  Applications for ultrahigh thermal conductivity graphite fibers , 1993, Optics & Photonics.

[30]  H. J. Hagger,et al.  Power travelling-wave tubes , 1965 .

[31]  R. S. Symons,et al.  Tubes: still vital after all these years , 1998 .

[32]  C.E. Hobrecht.  Resonant loss for helix traveling wave tubes , 1977, 1977 International Electron Devices Meeting.

[33]  Mark T. North,et al.  Porous media heat exchangers for cooling of high-power optical components , 1995 .

[34]  R. Harper,et al.  Heat transfer and power capabilities of EHF helix TWT's , 1986, 1986 International Electron Devices Meeting.

[35]  B. R. Gray,et al.  RF tubes for space-based accelerators , 1991 .

[36]  B. Hogan,et al.  Experimental studies of stability and amplification in a two-cavity second harmonic gyroklystron , 1994 .

[37]  E. Potenziani,et al.  Novel high-field permanent-magnet flux sources , 1987 .

[38]  V. A. Flyagin,et al.  The Gyrotron , 1977 .

[39]  A. Dybbs,et al.  Internal heat transfer coefficients of porous metals , 1982 .

[40]  Richard J. Temkin,et al.  Long-pulse and CW tests of a 110-GHz gyrotron with an internal, quasi-optical converter , 1996 .

[41]  Enhanced brightness x‐ray source , 1983 .

[42]  B. L. Jones.  Properties of natural and synthetic diamond. Edited by J. E. Field, Academic Press, London 1992, XIV, 710 pp., hardcover, £ 90, ISBN 01 2-255352-7 , 1993 .

[43]  T.A. Fox,et al.  Traveling-wave tube efficiency improvement with textured pyrolytic graphite multistage depressed collector electrodes , 1981, IEEE Electron Device Letters.

[44]  Claude A. Klein,et al.  CVD diamond for optics applications in high heat flux environments , 1996, Optics & Photonics.

[45]  R. Miller,et al.  Thermal Conductivity of Highly Oriented Pyrolytic Boron Nitride , 1976 .

[46]  G. Mclane,et al.  Fabrication of multipolar magnetic field sources , 1994 .

[47]  Mikhail A. Moiseev,et al.  Development of 1 mw output power level gyrotron for ITER , 1998 .

[48]  Max L. Lake,et al.  VGCF/carbon composites for plasma-facing materials , 1993, Optics & Photonics.

[49]  D.H. Preist,et al.  The klystrode—An unusual transmitting tube with potential for UHF-TV , 1982, Proceedings of the IEEE.

[50]  W. Rohsenow.  A Method of Correlating Heat-Transfer Data for Surface Boiling of Liquids , 1952, Journal of Fluids Engineering.

[51]  Lindon C Thomas,et al.  Heat Transfer: Professional Version , 1993 .

[52]  V. Granatstein,et al.  High-power X-band amplification from an overmoded three-cavity gyroklystron with a tunable penultimate cavity , 1992 .

[53]  Paul G. Klemens,et al.  Thermal conductivity of solids , 1977 .

[54]  A. S. Gilmour.  Principles of Traveling Wave Tubes , 1994 .