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Showing papers on "Breakdown voltage published in 1974"


Journal ArticleDOI
TL;DR: In this paper, a model for the incipient stages of intrinsic dielectric breakdown was proposed for a wideband gap insulator with a low hole mobility, and the model predicted an intrinsic breakdown voltage which approached a lower limit of V = 9+φ for very thin films, where φ is the cathode contact barrier in volts.
Abstract: A mechanism describing the incipient stages of intrinsic dielectric breakdown is formulated for the case of a wide‐band‐gap insulator with a low hole mobility. Dielectric instability results from the tunnel injection of electrons from the cathode contact and the subsequent impact ionization and field distortion which lead to dielectric breakdown. The model, evaluated for the parameters of SiO2, predicts an intrinsic breakdown voltage which approaches a lower limit of V=9+φ for very thin films, where φ is the cathode contact barrier in volts. As a result, both the electric field at breakdown and the critical current density increase rapidly as the film thickness is reduced below 200 A.

131 citations



Journal ArticleDOI
TL;DR: In this article, a high field region within the insulating layer where dielectric breakdown is initiated was found to be present in vacuum-evaporated Au-SiOx-Au thin film cathodes with insulator thicknesses ranging up to approximately 6000 A.
Abstract: Vacuum-evaporated Au-SiOx-Au thin film cathodes with insulator thicknesses ranging up to approximately 6000 A have been tested at direct voltages up to 60 V. In addition to exhibiting negative resistivity and single-hole dielectric breakdowns which have previously been observed at voltages leas than 20 V, these samples also showed a destructive breakdown mechanism at a voltage (V β) normally between 20 V and 30 V, which was independent of the insulator thickness. Increased device temperatures and wrinkling of the counter electrode indicated thermal processes at the voltage V β. These results may be explained in terms of a high field region within the insulating layer, where dielectric breakdown is initiated. The existance of such a region has previously been reported, and was confirmed in the present work.

36 citations


Journal ArticleDOI
TL;DR: In this article, a two-dimensional analysis technique for determining the drain voltage at the onset of either punch-through or avalanche breakdown, from a solution of Poisson's equation within the substrate depletion region, is described.
Abstract: A comprehensive investigation has been carried out into the factors which influence the maximum drain voltage of an M.O.S. transistor for normal pentode-like operation. The drain voltage is limited by two principal mechanisms, namely punch-through of the drain depletion region to the source, and breakdown, due to impact ionization in the high field region at the drain edge. A two-dimensional analysis technique for determining the drain voltage at the onset of either punch-through or avalanche breakdown, from a solution of Poisson's equation within the substrate depletion region, is described. The solutions are obtained using finite difference numerical methods which take into account the gate-induced potential profiles at the edge of the source and drain junctions. Boundary conditions of zero effective gate bias and channel current are imposed which simplify the solution of Poisson's equation to an electrostatic one. The punch-through voltage VPT is defined as the drain-to-source voltage at which the longitudinal field at any point along the edge of the source region inverts in sign to permit the drift of minority carriers from source to drain. Breakdown voltage, VBD, however, is determined by the drain voltage at which the maximum field in the device reaches the critical value for avalanche multiplication. Good agreement is achieved between theoretical and practical results for both mechanisms on a wide variety of devices. It is shown that VPT decreases as the channel length and substrate doping concentration decrease and as the oxide thickness and diffusion depth increase. VBD, however, decreases as the channel length, oxide thickness and diffusion depth decrease. Punch-through and breakdown are discussed for gate bias conditions above and below threshold. The sharp fall in breakdown voltage as the gate bias rises above threshold is explained on the basis of injected charge from the channel into the drain depletion region.

32 citations


Patent
15 May 1974
TL;DR: In this article, a semiconductor device is provided having at least two semiconductor regions of opposite conductivity type and forming a planar-type PN junction, where a field limiting ring is disposed spaced from the PN.
Abstract: A semiconductor device is provided having at least two semiconductor regions of opposite conductivity type and forming a planar-type PN junction. A field limiting ring is disposed spaced from the PN junction. A high-resistivity polycrystalline silicon layer covers the PN junction and the field limiting ring.

31 citations


Patent
01 May 1974
TL;DR: An improved insulated gate field effect transistor is achieved by using a material such as silicon nitride as an ion implantation and oxidation mask overlying a channel region, forming source and drain regions or extensions thereof by implanting ions of a conductivity modifier into a semiconductor substrate, and subjecting the implanted ions to a drive-in diffusion whereby the conductivity modifiers ions are redistributed.
Abstract: An improved insulated gate field effect transistor is achieved by using a material such as silicon nitride as an ion implantation and oxidation mask overlying a channel region, forming source and drain regions or extensions thereof by implanting ions of a conductivity modifier into a semiconductor substrate, and subjecting the implanted ions to a drive-in diffusion whereby the conductivity modifier ions are redistributed. The ion implantation allows greater control over the amount of conductivity modifier implanted in the lightly doped source and drain regions, the more uniform distribution of conductivity modifier increases the source-drain breakdown voltage, while the use of the silicon nitride mask provides simultaneously for general alignment of the channel region with the effective gate length.

30 citations


Journal ArticleDOI
TL;DR: In this article, the performance of Schottky-Read IMPATT diodes at X-band frequencies was investigated and the highest efficiency measured was 26.1 percent with 2.5-W continuous-wave (CW) output power at 8.8 GHz for a single-mesa diode while multiplemesa DAs have delivered more than 7 W at X band.
Abstract: High-efficiency performance of GaAs Schottky-Read IMPATT diodes has been observed at X-band frequencies. The highest efficiency measured was 26.1 percent with 2.5-W continuous-wave (CW) output power at 8.8 GHz for a single-mesa diode while multiple-mesa diodes have delivered more than 7 W at X band. The diodes were fabricated from multiple-layer epitaxial material with gold-plated heat sinks. Details of materials preparation and diode fabrication are presented. Theoretical calculations of diode breakdown voltage and efficiencies have been made as a function of the structural properties of the diodes. Good agreement has been obtained between the experimental microwave oscillator performance and the theoretical calculations.

27 citations


Journal ArticleDOI
TL;DR: In this paper, a computer-aided experimental procedure consisting in relaxation field calculations with boundary conditions governed by junction breakdown voltage (at given gate voltage) as measured on specially processed gate-controlled diodes.
Abstract: Surface breakdown in silicon planar junctions is analysed with emphasis on the evaluation of the critical field (i.e., the maximum electric field within the depletion region at breakdown). This parameter is determined by a computer-aided experimental procedure consisting in relaxation field calculations with boundary conditions governed by junction breakdown voltage (at given gate voltage) as measured on specially processed gate-controlled diodes. The idealization (infinite doping) of the highly doped side of the junction, encountered in previous works, has been eliminated. Values of the critical field determined are in the range of 1 × 10 6 V/cm (1·0 × 10 6 V/cm for 1·0 μm gate-oxide and 1·4 × 10 6 V/cm for 0·3 μm gate-oxide). These values are substantially higher than those estimated by other authors (5–6 × 10 5 V/cm) and are consistent with independent experimental findings on avalanche (hot-carrier) injection in silicon diodes.

23 citations


Journal ArticleDOI
TL;DR: In this article, the authors investigated the dependence of the prebreakdown current on the radius of curvature of the electrodes and the electrodes' insulator distance in an ultrahigh vacuum (UHV) setting.
Abstract: Measurements of the prebreakdown currents have been made for highly polished stainless‐steel electrodes in an ultrahigh vacuum (UHV) at 10−9 Torr as a function of electrode separation in the range 0.5–3.81 mm. Three sets of electrodes are employed to investigate the dependence of the prebreakdown current on the radius of curvature of the electrodes and the electrodes‐insulator distance. The breakdown potential is measured in UHV gaps over the gap length range 0.25–4.57 mm and in hydrogen, in the pressure range 3 × 10−9−1.5 × 10−2 Torr, over the gap length range 0.38–0.76 mm. It has been found that the breakdown voltage, the electric field enhancement factor, and the prebreakdown current are independent of electrode‐glass‐insulator distance in the range 1–12.65 mm for a fixed gap length and a fixed radius of curvature of the electrodes. On the other hand, increasing the radius of curvature of the edge of the flat electrodes, at a fixed gap length, results in (i) large increases in the prebreakdown currents, (ii) increase in the electric field enhancement factor at the cathode, and (iii) a decrease in the breakdown voltage. The addition of hydrogen causes an increase in both the prebreakdown currents and the field enhancement factor, at a fixed gap distance. The field enhancement factor at the cathode is determined from the Fowler‐Nordheim field emission theory and was found, in all cases, to increase initially with increasing gap length until saturation is reached, and therein it remains constant. The breakdown potential of vacuum gaps is found to follow a linear field‐emission dependence on gap separation up to 1 mm. At higher gaps a transition to the Cranberg clump mechanism is observed with a dependence law on distance to the power of 0.45. The critical electrical breakdown field at the cathode in high vaccum is determined to be (7.8 ± 1.3) × 109 V m−1.

22 citations


Patent
William F. Davis1
15 Nov 1974
TL;DR: An overvoltage protection circuit in an integrated circuit for increasing the breakdown voltage of the integrated circuit between first and second terminals thereof is presented in this article. But the circuit is not suitable for the use in a wireless sensor network.
Abstract: An overvoltage protection circuit in an integrated circuit for increasing the breakdown voltage of the integrated circuit between first and second terminals thereof. Diode-connected transistors are connected in series between the first terminal and a resistor. The resistor is connected to the base of a first transistor having its emitter connected to the second terminal and its collector connected to the base of a second transistor having its emitter connected to the second terminal and its collector connected to the first terminal. If an overvoltage applied between the first and second terminals exceeds the sum of the emitter-base reverse breakdown voltages of the diode-connected transistors, current flows into the base of the first transistor, causing it to saturate, thereby preventing the emitter-base junction of the second transistor from being forward biased. The collector to emitter breakdown voltage of the second transistor is thereby increased.

20 citations


Journal ArticleDOI
TL;DR: In this paper, the effects of dislocations on the SiO2/Si interface have been studied at dislocation levels of from 104 to 109/cm2, and no effects on the interface state density are seen.
Abstract: The effects of dislocations on the SiO2/Si interface have been studied at dislocation levels of from 104 to 109/cm2. At dislocation levels of 106/cm2 or less the MOS properties are unaffected; at levels from 107 to 109/cm2 the flat‐band voltage increases with dislocation density to the point where it is not measurable at 109 dislocations/cm2, being greater than the SiO2 breakdown voltage. No effects on the interface state density are seen.

Journal ArticleDOI
TL;DR: In this paper, a generalized quantitative criterion suitable for computer calculations of breakdown voltages in known fields in SF6 and other strongly electronegative gases is described, and it is shown that the anomaly in the uniform field gap breakdown voltage can be satisfactorily accounted for.
Abstract: Experiments showing anomalously low breakdown voltages in uniform field gaps in SF6 are discussed. A generalized quantitative criterion suitable for computer calculations of breakdown voltages in known fields in SF6 and other strongly electronegative gases is described, and it is shown that the anomaly in the uniform field gap breakdown voltages can be satisfactorily accounted for. Similar anomalies can occur in other field geometries and in other gases; it is shown how to avoid such breakdowns.

Patent
21 Mar 1974
TL;DR: In this paper, the radial dimensions of the electrodes and the tubular portions of the enclosure are chosen so that the d.c. ignition voltage of the arrester is lower than the breakdown voltage between the electrodes.
Abstract: In an excess voltage arrester comprising a pair of spaced electrodes housed in a gas-filled enclosure the electrodes extending towards one another from end caps through respective tubular insulating portions of the enclosure so that the gap between the electrodes lies within a central conductive tubular portion of the enclosure, the radial dimensions of the electrodes and the tubular portions of the enclosure are chosen so that the d.c. ignition voltage of the arrester is lower than the breakdown voltage between the electrodes and sputtered coatings which may form on the internal surfaces of the insulating portions of the enclosure.

Patent
23 Jul 1974
TL;DR: In this paper, a voltage divider having a division tap point is connected in parallel to the main switching part of the switching transistor of the ignition system, and typically a voltage breakdown element, typically a Zener diode is connected from the tap point to the control electrodes of the semiconductor switch to provide an additional control voltage to compensate for the voltage exceeding a value leading to breakdown of the breakdown device.
Abstract: To improve the operation of semiconductor control ignition systems under widely varying supply voltage conditions, a voltage divider having a division tap point is connected in parallel to the main switching part of the switching transistor of the ignition system, and a voltage breakdown element, typically a Zener diode is connected from the tap point to the control electrodes of the semiconductor switch to provide an additional control voltage thereto if the voltage at the tap point exceeds a value leading to breakdown of the breakdown device (Zener diode); the main control circuit for the main ignition transistor may be conventional.

Journal ArticleDOI
TL;DR: In this article, a theoretical analysis of the field distribution near the surface of p-n-p structures with double positive edge geometry was made, and the results showed that the reduction of the maximum field at the surface is not as easy as for the case of a simple positive bevel angle and that consequently the passivation of the surface may present more problems.
Abstract: A theoretical analysis is made of the field distribution near the surface of p-n-p structures with double positive edge geometry. This geometry offers in principle the possibility of avoiding the limitations and disadvantages inherent in the use of negative bevel angles. The results show that the reduction of the maximum field at the surface is not as easy as for the case of a simple positive bevel angle and that consequently the passivation of the surface may present more problems. Nevertheless, it is demonstrated that this geometry offers a number of great advantages and presents a real alternative for use in future high-voltage devices. A number of devices, dimensioned for a breakdown voltage of 6 kV, were made with this edge geometry. The measurements show that the reverse current corresponds to the thermally generated current in the space-charge layer and that no significant current flows at the surface. The breakdown voltage corresponds to the theoretical breakdown voltage in the bulk, unlike in the case of double negative beveling. The advantages of this geometry with respect to the conventional negative bevel angle are no significant reduction of active area, no dependence on the doping profile, and no limitation in voltage. A disadvantage, however, is the presence of higher fields at the surface.

Journal ArticleDOI
TL;DR: In this paper, the dc breakdown potential of a pointplane electrode configuration is measured in high vacuum (∼10−7 Torr) using the positive and the negative voltage polarity of the point electrode as a function of gap separation.
Abstract: The dc breakdown potential of a point‐plane electrode configuration is measured in high vacuum (∼10−7 Torr) using the positive and the negative voltage polarity of the point electrode as a function of gap separation Air, nitrogen, helium, sulphur hexafluoride, and argon are used in turn to alter the electrode coverage by adsorption of various gases in high vacuum It has been found that helium gives the highest breakdown voltage at a given gap length, in high vacuum It has also been found that very high sparking potential values are obtained using positive‐point‐negative‐plane electrodes (90 kV at 03 mm gap length, helium at 3×10−7 Torr) The effect of ac (50 Hz) glow discharge conditioning on the dielectric strength of the gap is investigated and found to give considerable improvement in the voltage that the gap can withstand before a vacuum breakdown occurs The effect of introducing various gases in the pressure range 10−7−10−2 Torr on the breakdown potential of point‐plane gaps is investigated Maxima are observed in the breakdown voltage and pressure curves in the range 10−4−10−3 Torr Helium and nitrogen give the highest breakdown voltage of about 90 kV for a gap length of 02 mm at about 10−4 Torr The observed improvements in the breakdown potential that the gap can withstand with certain gases are attributed to the increase in the work function of the combined metal‐gas system

Patent
08 Feb 1974
TL;DR: In this paper, a method for precisely tailoring the thickness of a layer of semiconductor material in a structure comprising regions of varying doping concentrations in order to achieve desired uniform electrical properties is presented.
Abstract: A method for precisely tailoring the thickness of a layer of semiconductor material in a structure comprising regions of varying doping concentrations in order to achieve desired uniform electrical properties. The method involves, generally, electrolytically thinning the layer to remove the semiconductor material until a desired field distribution in the structure is reached. In one embodiment, an FET with an epitaxial layer on a semi-insulating substrate is manufactured by successively oxidizing the epitaxial layer and dissolving the oxide until the depletion region resulting from the applied potential extends into the semi-insulating substrate and oxide growth stops. This results in a uniform pinch-off condition along the layer regardless of the original non-uniformity in the epitaxial layer. In a further embodiment, the epitaxial layer in an IMPATT structure is thinned by successive oxidation and dissolution until the voltage dropped across the semiconductor is equal to the applied potential and again oxide growth stops. This procedure results in a desired uniform breakdown voltage for the wafer.

Journal ArticleDOI
TL;DR: In this article, the authors evaluated the switching impulse (S.I.) breakdown voltage of tower window models of different sizes and found that the 50% breakdown voltage was determined for seven different wavefronts with a time-to-crest between 60 and 800 ps and a half-amplitude time over 3500 ps.
Abstract: Tests were performed to evaluate the switching impulse (S.I.) breakdown voltage of tower window models of different sizes. Window models were tested with positive polarity S.I. and with conductor-to-structure clearances of 4.55, 5.90, 7.60 and 8.75 meters. With each size of model the 50% breakdown voltage was determined for seven different wave-fronts with a time-to-crest between 60 and 800 ps and a half-amplitude time over 3500 ps. The time-to-breakdown was also recorded and correlated to the time-to-crest of the applied wave and the breakdown voltage.

Journal ArticleDOI
TL;DR: In this paper, it was observed that micron and submicron-sized particles are released in abundance well below the breakdown voltage, indicating that the microparticles are composed of the electrode materials.
Abstract: According to Cranberg's hypothesis, tiny aggregates of metallic matter called microparticles, emanating from the electrode surfaces, are responsible for the breakdown of a vacuum gap under high dc stress. Experiments are carried out using a scanning electron microscope to see whether such particles appear within the interelectrode gap prior to breakdown. It was observed that micron‐ and submicron‐sized particles are released in abundance well below the breakdown voltage. Investigations were continued to identify the microparticles with the electrode materials using an electron microprobe analyzer. It was found that the microparticles were composed of the electrode materials. Direct examination of the electrode surfaces, after application of the voltage, under the scanning electron microscope also showed features suggesting that the microparticles are released from the electrode surfaces.

Journal ArticleDOI
TL;DR: In this article, the Fowler-Nordheim field emission theory was used to measure the breakdown voltage, the current at initiation of the discharge, the field enhancement factor, and the current density and emitting area at breakdown as a function of the number of breakdowns.
Abstract: Measurements of prebreakdown current as a function of applied electric field have been made for polished stainless steel electrodes in vacuum (similar 10−8 mm Hg) for gap separations 002

Journal ArticleDOI
TL;DR: In this paper, an explanation for the higher sparking potential values of the Paschen minimum measured in concentric coaxial fields compared to uniform fields is given, and the failure of the similarity theorem in some gases when applied to the sparking potentials in uniform fields at the PASChen minimum is attributed to non-equilibrium ionization effects.
Abstract: An explanation for the higher sparking potential values of the Paschen minimum measured in concentric coaxial fields compared to uniform fields is given. The failure of the similarity theorem in some gases when applied to the sparking potentials in uniform fields at the Paschen minimum is attributed to non-equilibrium ionization effects.

Journal ArticleDOI
TL;DR: In this paper, the annealing characteristics of 50 −keV (2 −3) × 1011/cm2 11B+-implanted p-channel MOS transistors were investigated from 300 to 900°C.
Abstract: The annealing characteristics of 50‐keV (2–3) × 1011/cm2 11B+‐implanted p‐channel MOS transistors were investigated from 300 to 900°C. Below 500°C, the number of activated atoms NII decreased rapidly with decreasing anneal temperature and the C‐V characteristics showed gradual distortions. This was presumably due to surface states induced by the ion implantation. Above 500°C, NII increased only slightly with increasing anneal temperature and the slope of the C‐V characteristics in the transition region was larger than that of the unimplanted sample. Corresponding to the above features, the gain term increased near 500°C to a value about 30% larger than that of the unimplanted sample, while the breakdown voltage decreased below 500°C. Equivalent noise voltage decreased abruptly from 500 to 600°C. However, at lower drain current levels, the generation‐recombination noise spectrum did not disappear, even after a 900°C anneal. In addition, reverse‐annealing‐like phenomena were observed in the equivalent noise...

Journal ArticleDOI
TL;DR: In this article, the authors measured the pre-breakdown current and breakdown voltage between aluminium, copper, stainless steel, niobium and gold electrodes in vacuum and uniform fields at room, liquid nitrogen and liquid helium temperatures.
Abstract: These investigations were conducted to measure the prebreakdown current and breakdown voltage between aluminium, copper, stainless steel, niobium and gold electrodes in vacuum and uniform fields at room, liquid nitrogen and liquid helium temperatures. The range of electrode spacings for the current measurements was 0·1-4 mm and for the breakdown voltages was 0·1-1·8 mm. The results showed that the current decreased with decreasing electrode spacing and decreasing cathode temperature. They also showed that the breakdown voltage increased with increasing electrode spacing and decreasing cathode temperature. It was shown that the prebreakdown currents obeyed a cold-cathode emission law analytically similar to the Fowler-Nordheim relation and that the changes in values could be explained by changes in the field intensification factor and emitting area. The breakdown voltages indicated that the same mechanism prevailed at all spacings and temperatures and suggested that breakdown was initiated by the cold-cathode emission currents causing an instability at either the anode or the cathode.

Journal ArticleDOI
01 Apr 1974
TL;DR: In this article, a representation based on the similarity relations for voltage breakdown is shown to be useful in combining RF and dc voltage breakdown data, and the representation for the uniform field geometry is given.
Abstract: A representation based on the similarity relations for voltage breakdown is shown to be useful in combining RF and dc voltage breakdown data. The representation for the uniform field geometry is given.

Proceedings ArticleDOI
01 Jan 1974
TL;DR: In this paper, the breakdown strength of liquid helium boiling at atmospheric pressure, under voltages up to ± 130 kV de, and in gaps of up to 2.5 mm.
Abstract: In a previous paper,1 a program underway at Oak Ridge National Laboratory to investigate the high voltage electrical properties of fluids and solids for cryogenic systems was described. As the first result of these investigations, we report here on measurements of the breakdown strength of liquid helium boiling at atmospheric pressure, under voltages up to ± 130 kV de, and in gaps of up to 2. 5 mm. Preliminary results with ac voltage have also been obtained.

Patent
28 Jun 1974
TL;DR: In this paper, a high-voltage power transistor is described which is able to withstand fluences as high as 3 × 10 14 neutrons per square centimeter and still be able to operate satisfactorily.
Abstract: A high-voltage power transistor is hereinafter described which is able to withstand fluences as high as 3 × 10 14 neutrons per square centimeter and still be able to operate satisfactorily. The collector may be made essentially half as thick and twice as heavily doped as normally and its base is made in two regions which together are essentially four times as thick as the normal power transistor base region. The base region has a heavily doped upper region and a lower region intermediate the upper heavily doped region and the collector. The doping in the intermediate region is as close to intrinsic as possible, in any event less than about 3 × 10 15 impurities per cubic centimeter. The second base region has small width in comparison to the first base region, the ratio of the first to the second being at least about 5 to 1. The base region having the upper heavily doped region and the intermediate or lower low doped region contributes to the higher breakdown voltage which the transistor is able to withstand. The high doping of the collector region essentially lowers that portion of the breakdown voltage achieved by the collector region. Accordingly, it is necessary to transfer certain of this breakdown capability to the base region and this is achieved by using the upper region of heavily doped and an intermediate or lower region of low doping.

Proceedings ArticleDOI
01 Oct 1974
TL;DR: In this paper, the voltage life of cross-linked polyethylene (XLPE) was determined by visible unhomogeneous micro-deterioration "microtrees" in the insulation.
Abstract: Many organic insulating materials have voltage lives but the mechanism determining the voltage lives has not been established. In the case of cross-linked polyethylene (XLPE), by using a new experimental method, we observed that visible unhomogeneous micro-deterioration “microtrees” occurred in the insulation. We concluded that the voltage lives may be determined by these microtrees.

Patent
12 Aug 1974
TL;DR: An active circuit and method for increasing the operating range of circuit elements of the type connected between a power supply and a circuit element, the active circuit including a transistor including a base, emitter and a collector, the transistor having a breakdown voltage as mentioned in this paper.
Abstract: An active circuit and method for increasing the operating range of circuit elements of the type connected between a power supply and a circuit element, the active circuit including a transistor having a base, emitter and a collector, the transistor having a breakdown voltage. The transistor is biased to provide a current path through it to the circuit element and to develop a voltage thereacross. The transistor and its biasing in combination are operative when the supply voltage exceeds a predetermined level to cause the transistor to breakdown. The breakdown voltage across the transistor opposes the supply voltage so that the operating range is increased and the actual voltage applied to the element does not exceed the breakdown voltage of the element.

Journal ArticleDOI
P. Brook1
TL;DR: The breakdown voltage of an abrupt double-sided junction is a function only of N eff (the doping obtained from capacitance-voltage analysis) in a material in which the ionization rates for electrons and holes are equal or maintain a constant ratio as mentioned in this paper.
Abstract: The avalanche breakdown voltage of an abrupt double-sided junction is a function only of N eff (the doping obtained from capacitance-voltage analysis) in a material in which the ionization rates for electrons and holes are equal or maintain a constant ratio. This doping parameter, together with the published breakdown voltage data for single-sided junctions, immediately gives the breakdown voltage of the more complex structure.

Journal ArticleDOI
TL;DR: In this article, ten types of particles commonly found in electron tubes were tested for their effects on high-voltage breakdown and interelectrode current and it was found that insulating particles lower the breakdown voltage as much as 30% but the electrodes can be easily conditioned with little damage.
Abstract: Ten types of particles commonly found in electron tubes were tested for their effects on high-voltage breakdown and interelectrode current. The particles were applied to stainless steel electrodes and then tested for initial breakdown voltage, number of breakdowns necessary to condition the electrodes, and interelectrode current after high-voltage conditioning. It was found that insulating particles lower the breakdown voltage as much as 30% but the electrodes can be easily conditioned with little damage. Conducting particles and amorphous carbon particles lower the breakdown voltage up to 45%. In addition, these particles cause severe high-voltage conditioning problems. There is much more arcing during conditioning which results in severely damaged electrode surfaces. The arc craters are then a source of interelectrode leakage.