Conduction in Nb/Nb2O5/In structures is strongly thickness dependent. Both present and previous data are interpreted by the model of an overlap MIM structure. In this model, conduction is through space-charge-limited flow of electrons injected from the metal electrode but the electrodes change the electron density in the oxide considerably due to the overlap of the two contact space-charge regions. Die Leitfahigkeit in Nb/Nb2O5/In-Strukturen ist stark dickenabhängig. Sowohl die angeführten als auch frühere Werte werden mit dem Modell einer überlappenden MIM-Struktur interpretiert. In diesem Modell wird die Leitfähigkeit durch raumladungsbegrenzten Fluß von Elektronen hervorgerufen, die aus der Metallelektrode injiziert werden, jedoch ändern die Elektroden die Elektronendichte im Oxid infolge der Überlappung der beiden Kontaktraumladungsbereiche beträchtlich.

It is shown that contact overlap in a MIM structure with distributed traps depends on the trap density per unit energy and that the conductivity of the structure depends strongly on the insulator thickness over a certain range which is determined by a characteristic length. The variation of the conductivity with thickness can be stronger than that of a structure with a shallow discrete trap level. Es wird gezeigt, daß die Kontaktüberlappung in einer MIM-Struktur mit verteilten Haftstellen von der Haftstellendichte pro Energieeinheit abhängt und daß die Leitfähigkeit der Struktur über einen gewissen Bereich, der durch eine charakteristische Länge bestimmt ist, stark von der Isolatordichte abhängt. Die Änderung der Leitfähigkeit mit der Dicke kann größer sein als die einer Struktur mit einem diskreten flachen Haftstellenniveau.

The effect of the ohmic contacts on the current-voltage characteristics of a thin unipolar metalinsulator-metal structure is presented. It is shown that the conductivity of such MIM structures is a function of contact overlap in which space-charge layers in the contact regions extend into the insulator from both contacts. It strongly depends on the insulator thickness over a certain range which is determined by a characteristic length. Es wird der Einfluß der Ohmschen Kontakte auf die Strom-Spannungscharakteristiken von dünnen unipolaren Metall-Isolator-Metall-Strukturen untersucht. Es wird gezeigt, daß die Leitfähigkeit von derartigen MIM-Strukturen eine Funktion der Kontaktüberlappung ist, indem Raumladungsschichten in den Kontaktbereichen sich von beiden Kontakten in den Isolator erstrecken. Sie hängt in einem bestimmten Bereich, der durch eine charakteristische Länge bestimmt ist, stark von der Isolatordicke ab.

physica status solidi (a)Volume 83, Issue 1 p. K87-K92 Device-related phenomena Damage induced degradation of metal contacts on gallium arsenide J. Ejimanya, J. Ejimanya Department of Electrical and Electronic Engineering, University of Leeds Search for more papers by this authorD. V. Mofgan, D. V. Mofgan Department of Electrical and Electronic Engineering, University of Leeds Search for more papers by this author J. Ejimanya, J. Ejimanya Department of Electrical and Electronic Engineering, University of Leeds Search for more papers by this authorD. V. Mofgan, D. V. Mofgan Department of Electrical and Electronic Engineering, University of Leeds Search for more papers by this author First published: 16 May 1984 https://doi.org/10.1002/pssa.2210830169Citations: 1 Leeds LS2 9JT, Great Britain. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume83, Issue116 May 1984Pages K87-K92 RelatedInformation

Unimplanted n-type GaAs epitaxial layers have been annealed under the same conditions as those required to activate ion implants. If the duration of the anneal is sufficiently long (e.g. 10 min at 800°C) acceptor ions accumulate at the surface with a concentration of about 2×1022 m−3. Schottky contacts to annealed samples always show increased current densities up to six orders of magnitude greater than those in unannealed layers. This has the effect of lowering the Q values of varactor diodes made out of this material, up to frequencies of 1 GHz.

GMR is a useful technique for investigating the electron transport phenomena of semiconductors. The analysis is well suited to transferred electron device structures, and yields the carrier mobility. The galvanomagnetic coefficients and mobilities of gallium arsenide are determined by an accurate numerical solution of the Boltzmann transport equation. The GMR technique is illustrated by a study of the mobility of carriers in transferred electron diodes showing close agreements between the measured mobilities and the values determined from the numerical solution. GMR stellt eine nützliche Methode zur Untersuchung der Elektronentransporterscheinungen in Halbleitern dar. Die Analyse ist gut geeignet für Elektronentransferbauelementestrukturen und liefert die Trägerbeweglichkeit. Die galvanomagnetischen Koeffizienten und die Beweglichkeiten von Galliumarsenid werden durch genaue numerische Lösung der Boltzmanntransportgleichungen bestimmt. Die GMR-Technik wird anhand einer Untersuchung der Trägerbeweglichkeiten in Elektronentransferdioden illustriert, die eine enge Übereinstimmung zwischen den gemessenen Beweglichkeiten und den aus der numerischen Lösung bestimmten Werten zeigt.

In the review the processes of ion implantation and ion damage in GaAs and InP are considered. A survey of the basic physics of the implantation/damage processes is outlined together with detailed studies on the annealing required to activate the ions for semiconductor doping. The prospects and current achievements of this technological process in device fabrication are discussed in detail.

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation S. D. Mukherjee, D. V. Morgan, C. J. Palmstrom, J. G. Smith; Erratum: The thermal stability of thin layer transition and refractory metallizations on GaAs [J. Vac. Sci. Technol. 17, 904 (1980)]. J. Vac. Sci. Technol. 1 January 1981; 18 (1): 111. https://doi.org/10.1116/1.570686 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAVS: Science & Technology of Materials Interfaces and ProcessingJournal of Vacuum Science and Technology Search Advanced Search |Citation Search

The creation of atomic displacement damage in gallium arsenide crystals by ion implantation is now an established technique, utilized in the fabrication of devices. This survey describes past and current work at the University of Leeds, which is directed towards two objectives. The characterization and stability of radiation-induced defiects in gallium arsenide and the potential use of such damage layers in device fabrication.

Charge storage on aluminium oxide films has been studied using the Kelvin probe technique. The experiments extend previous studies by considering oxide films ranging in thickness from 3 nm up to 240 nm. The band structure of the oxide film deduced from these measurements is discussed and related to the problem of arc root initiation in oxide covered cathodes.

Interdiffusion and degradation of Cr/Pt/Ag multiple metallization layers for silicon IMPATT diode applications have been studied experimentally using Rutherford backscattering analysis, secondary ion mass spectrometry, and scanning electron microscopy. Diffusion coefficients for grain boundary diffusion and grain boundary‐assisted bulk diffusion of Pt in Ag and the corresponding activation energies have been determined. The effect of time on grain boundary diffusion showing rapid initial growth and eventual saturation of solute (Pt) in Ag grains has been studied in detail and its effect on device failure caused by the possible depletion of the Pt barrier layer is discussed. Samples annealed in air showed substantial degradation of the Ag layer due to chlorine contamination. The Cr/Pt interface has been found to be stable up to 400°C but annealing at or above 500°C caused considerable mixing between Si, Cr, and Pt.

In this paper, we discuss a numerical optimization technique which may be used to study the effect of interface states on the terminal characteristics of Schottky-barrier devices. The numerical technique is based on the minimization of the sum of residuals obtained by comparing accurate experimental data with a generalized theoretical model. The analysis used in the present study is based on Heine's model and takes the interfacial charges into account. The terminal characteristics of Au-Si Schottky-barrier devices are studied and analyzed. Information regarding interface state density, barrier height, etc., is obtained by using the optimization procedure in conjunction with the current-voltage and capacitance-voltage characteristics of these devices. Consistent values for the device parameters have been obtained through the utilization of the optimization technique.

The FM noise performance of oscillator modules based on GaAs transferred electron devices characterized by carrier notches close to the cathode contact is presented. The notches have been incorporated into completed and encapsulated devices by ion-implantation techniques, the notches proving stable up to 400°C. Useful improvements in the FM noise performance close to the carrier are available usin...

Chemischer InformationsdienstVolume 10, Issue 41 Physical Inorganic Chemistry ChemInform Abstract: INTERDIFFUSION AND DEGRADATION OF SILICON/CHROMIUM/PLATINUM/SILVER IMPATT (IMPACT AVALANCHE TRANSIT TIME) DIODE METALLIZATION S. D. MUKHERJEE, S. D. MUKHERJEESearch for more papers by this authorD. V. MORGAN, D. V. MORGANSearch for more papers by this authorM. J. HOWES, M. J. HOWESSearch for more papers by this author S. D. MUKHERJEE, S. D. MUKHERJEESearch for more papers by this authorD. V. MORGAN, D. V. MORGANSearch for more papers by this authorM. J. HOWES, M. J. HOWESSearch for more papers by this author First published: October 9, 1979 https://doi.org/10.1002/chin.197941017Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume10, Issue41October 9, 1979 RelatedInformation

The effects of various heat treatments on the surface of GaAs crystals have been studied using Rutherford scattering and channelling of alpha particles. The heat treatment was in the form of isochronal anneals in the temperature range 350–750°C. The crystals were heated in both flowing dry nitrogen and in vacuum (∼ 10−6 torr). The changes in surface-stoichiometry and surface disorder were measured and the results, for both free and silicon oxide passivated surfaces, are discussed.

A series of metals (namely Pt, Ni, Al, Cr, Ti, Ta, Mo, and W) were considered and investigated metallurgically as possible candidates for Schottky barrier metals for high-power GaAs IMPATT diode and FET applications. Interdiffusion, compound formation, lack of adhesion, and stability against humid and oxidizing atmospheres were studied in the temperature range of 250°–550°C using Rutherford backscattering of 2.0–2.25-MeV helium ions, secondary ion mass spectrometry (CAMECA IMS 300), and scanning electron microscopy with energy-dispersive x-ray analysis facility. In this paper we discuss the results and attempt to classify the metals qualitatively into four groups according to the main degradation mechanisms which are likely to limit their use as a Schottky barrier at high operating temperatures.