Showing papers on "p–n junction published in 1972"

Impurity centers in PN junctions determined from shifts in the thermally stimulated current and capacitance response with heating rate

Abstract: A theory is developed for the thermal response of pn junction current and capacitance where the junction contains deep impurity centers. Measurements lead to values for the energy level, emission coefficient and concentration of these centers. Energy levels and emission coefficients are found from shifts in either the current maxima or the capacitance slope maxima with heating rate. The theory indicates that the heating rate may be non-linear and that energy levels may be found independent of the emission coefficient. The analysis accounts for the possibility that only a portion of the space-charge region may contain charged deep centers. This allows the identification of centers in a small segment of the space-charge region. In addition, the analysis allows for the motion of the space-charge width as deep centers discharge. A gold-doped silicon n + p junction is used to verify the theory. The experimental hole emission parameters for the gold donor are in good agreement with those values obtained by other workers using different methods.

Light amplifier using a semiconductor

Abstract: A light amplifier using a semiconductor, in which an elongated single semiconductor PN junction is used for amplifying an input light injected at an input face provided at one end of the PN junction along the junction plane of the PN junction. The semiconductor PN junction is driven by bias signals applied at a common ohmic electrode and a plurality of ohmic electrodes respectively provided at opposite sides of the PN junction with respect to the junction plane. A plurality of the ohmic electrodes are sequencially arranged overlying the PN junction in a longitudinal direction and are electrically isolated from one another, so that a plurality of discrete regions are provided in the PN junction corresponding to the respective electrodes. Two adjacent regions are employed as one unitary region and are driven by predetermined different forward bias currents to bias one of the two regions as an amplifying region and the other of the two regions as a saturable absorbing region. The amplifying region is disposed at the input side while the saturable absorbing region is disposed at the output side in each unitary region. The respective unitary regions are connected in cascade to provide a plurality of the unitary regions.

p‐n Junction Photodiodes in PbTe Prepared by Sb+ Ion Implantation

Abstract: n‐p junction photovoltaic detectors in PbTe have been fabricated using Sb+ ion implantation to create the n‐type layer. At 77 °K, 15‐mil square diodes have had zero‐bias resistances as high as 15 MΩ for a resistance‐area product of 2.1×104 Ωcm2. Peak detectivities at 4.4 μm in reduced background as high as 1.6×1012 cmHz1/2/W were observed. Diode quantum efficiencies were typically 40% at 4.4 μm.

Silicon carbide junction thermistor

Abstract: A high impedance, junction thermistor for sensing temperatures from about -200*C. to above 1,400*C. is provided with a semiconductor body of silicon carbide. The silicon carbide semiconductor body has at least first and second impurity regions forming a PN junction therebetween. The temperature is sensed by the impedance response across the PN junction.

Apparatus and method for detection of internal semiconductor inclusions

Abstract: An apparatus for detecting the presence of inclusions in semiconductor material having a polychromatic light source, a support for a semiconductor body, a light sensing means positioned to operate on light transmitted through the body from the light source, the sensing means including a substrate of the same type of semiconductor materials as the material of the semiconductor body, and having at least a PN junction in the substrate with means to backbias the junction, a means to indicate the relative amounts of light transmitted through the semiconductor body that is sensed by the sensing means.

General transport theory of noise in PN junction-like devices—II. Carrier correlations and fluctuations for high injection

Abstract: A computation is given of the hole-density spatial correlation function in the N -region of a one dimensional P + N junction in the high-injection limit. Recombination processes which involve transitions through Shockley-Read levels with arbitrary capture ratio for electrons and holes (expressed by the parameter y = τ n 0 / τ p 0 ) are considered. Contrary to the low injection case or to high injection with quasi band-band recombination the covariance function shows a delta-function part which represents an approximation for correlations on a molecular scale, and a long-range part (for y ≠ 1) which persists over many diffusion lengths. This behaviour is in accord with general predictions for correlations in a non-equilibrium, non-homogeneous system. The density spectra are calculated next. Computer computations indicate smooth spectra for x = x ′, with a plateau for small ω and ω − 1 2 asymptote for large ω; the spectra for x ≠ x ′ oscillate between negative and positive values. Finally, these results are used to compute the derivative spectra and the junction current noise, and the low and high frequency behaviour is discussed. The asymmetry of the SR levels modifies the noise by as much as 33 per cent, but the general trends of the previous high injection results [1] are confirmed. I.e., for small ω there is a slight reduction in noise for P + N junctions, depending on b (mobility ratio), γ (hole current fraction) and y (SR parameter). For an N + P junction a noticeable enhancement is predicted.

10 GHz Si Schottky-barrier IMPATT diode with hyperabrupt impurity distribution produced by ion implantation

Abstract: Ion implantation has been combined with a Schottky-barrier to make a Read type Si IMPATT diode for 10 GHz operation. Phosphorus ion implantation at 300 keV produced the hyperabrupt impurity distribution and a platinum-silicide Schottky-barrier replaced the pn junction in the original Read structure. This combination of techniques makes it possible to introduce a very precise amount of impurity and thus makes the Read diode a more practical device than before. The Schottky barrier also supresses the minority-carrier storage effect which is believed to reduce oscillation efficiency. An efficiency of 10·7 per cent was observed with 510 mW output at a bias current density of 500 A/cm 2 , which is about 1 2 of the current density typically required for the presently standard, abrupt-junction diode.

Inverse gate semiconductor controlled rectifier

Abstract: An inverse gate semiconductor controlled rectifier device including a base region, and main and auxiliary emitter regions respectively forming a main and auxiliary PN junction with the said base region is provided with a conductive layer located on the surface of the base region in ohmic contact therewith and extending from adjacent the auxiliary emitter junction to alongside an edge of the main emitter junction but not of itself bridging either the main or auxiliary junction. The conductive layer, in operation, expands a preferential current path between the auxiliary emitter and main emitter along the said edge.

Effects of Impurities on Gamma-Irradiated Silicon Crystal Examined by Photovoltaic Effect of P - N Junction Diode

Abstract: Minority carrier lifetime in 60Co gamma-irradiated silicon bulk crystals is examined by photovoltaic effect of silicon p-n junction, and following results are disclosed. 1) Damage constant, K, increases with impurity concentration of bulk crystals. K is smaller in p-type crystals than in n-type. 2) For isochronal annealing, recovery stages of n-type bulk crystals at 100–150°C and 300°C are found. In p-type crystals, reverse annealing is observed at 200–300°C. 3) From the temperature dependence of carrier lifetime, energy levels of the recombination centers at Ec-0.42 for n-type and Ev+0.32, Ev+0.25 eV for p-type crystals are found. 4) Recovery stage of p-type bulk crystals due to gamma irradiation at 81 K is observed at about 150 K, but that of n-type is not observed between 80 and 300 K. 5) The lifetime degradation in p-type crystals due to gamma irradiation at 81 K is reduced when minority carrier is injected after the irradiation.

P-n junction semiconductor devices

Abstract: To produce a P-conductivity type wide band gap semiconductor material, a III-V compound semiconductor layer is first vacuum evaporated onto and then diffused into a crystalline II-VI compound semiconductor substrate, specifically a zinc chalcogenide. The resulting crystalline material is doped by simultaneous or sequential infusion of zinc atoms in substitution for atoms of the Group III element. The process may be used for the direct production of P-N junctions in zinc chalcogenides by employing an N-type rather than an intrinsic substrate.

On the carrier generation-recombination in the space-charge region of a p-n junction†

Abstract: In this paper the gradual capture effect on the goneration-recombination current in the space-charge region for an asymmetrical junction is studied. The theory ia applied to the p+-n InSb diodes. At forward bias, when the lifetime increases in the direction from p+ region to n region, the results we have obtained show that the current increases more rapidly ivith voltage than in the reverse case.

Some properties of reverse-biased silicon carbide p - n junction cold cathodes

Abstract: An analysis is made of the changes occurring in the electrical characteristics of reverse-biased p-n junction electron emitters in SiC during the development of emission. The functional dependence of the emission on the junction voltage, current, mean cathode temperature and extraction field is investigated, and it is shown that the emission is directly proportional to the surface component of the junction current, which can be separated from the bulk current through the p-n junction. Emission is developed at points along the p-n junction by thermal processing, the magnitude of which determines the level of the emission, which is then stable at all lower values of power dissipation. The possibility of increasing the emission by pulsing the junction current is also examined.

Thermal analysis of p—n junction second breakdown initiation†

Abstract: An experimental and theoretical investigation of the thermal initiation of second breakdown in p-n diodes and bipolar transistors is presented. Since the experimental work is performed under closely controlled non-destructive conditions the results may be meaningfully related to the theoretical predictions obtained from a distributed thermal model. The validity of an intrinsic triggering temperature concept is examined and found to be applicable under the experimental conditions described.

Analysis of the p-n junction second breakdown mode†

Abstract: A theoretical and experimental investigation of the p-n junction second breakdown mode is roported. By means of two simple models expressions are derived for the second breakdown terminal voltage which indicate the influence of device heat-sink conditions on the observed current-voltage characteristics in the low-voltage mode. Various experimental results are presented in support of the theoretical work, and a method is suggested for estimating maximum possible constriction temperatures.

Admittance of a forward-biased P-N + junction diode

Abstract: Numerical solutions of the basic semiconductor transport equations are used to analyze the ac behavior of a forward-biased diode.

Voltage-controllable capacitor

Abstract: 1283383 Semi-conductor devices GENERAL ELECTRIC CO 26 Sept 1969 [10 Oct 1968] 47576/69 Heading H1K The capacitance associated with PN-junction 20, 24 is greatly increased by the formation of an inversion region of controllable extent under capacitative electrode 17, 15A. Electrode layer 17 (with terminals 11/33 and 12/34) is resistive so that an increasing control potential applied to the electrode (12) nearest the PN junction leads to the formation of an inversion layer extending increasingly from the junction. A less-thaninverting voltage obtained from potentiometer 31 at the other end of this layer determines the value of the voltage at the junction end of the electrode at which inversion first occurs. That part only of electrode 17 is effective which lies on the thinner part 15A of the insulation 15. The shape of the control voltage-capacitance characteristic may therefore be tailored by suitably shaping the thinner area of insulation or by providing a shaped electrode 17 on part only of the thinner area (see Figs. 10 and 11, not shown). In embodiments the semi-conductor body is of silicon; the insulator layer 15, 15A is of silicon dioxide; the terminals 11, 12 are of molybdenum; the resistive layer 17 is of chromium nitride or of amorphous silicon; protective insulation 21 for the resistive layer is of silicon nitride; overlying insulation 18 is of phosphosilicate or borosilicate glass if the diffused zone 20 is formed near the end of the manufacture or is of undoped material if the junction is formed near the beginning of the manufacture; and terminal layers 25, (26), and 27 are of aluminium. The capacitor may be an individual device or may form part of an integrated circuit such as one containing IGFETs formed during common processing steps.

Differential d.c. conductance of a p-n-junction space-charge region

Abstract: It is shown that the differential d.c. conductance under reverse bias can be correctly obtained from the lumped approximation of the small-signal distributed-transmission-line model if the true majority-carrier concentration in the edge region of the space-charge layer is taken into account.

Double Pulse Measurements of Avalanching p‐n Junction Submicrosecond Transient Thermal Response

Abstract: A method is presented for measuring the transient thermal response of avalanching p‐n junctions. The transient response as close as 50–100 nsec after the step‐like change of the power dissipation at the junction can be measured with an accuracy of ±0.4°C and about 40 nsec. Experiments show a sharp change of junction temperature, approaching closely the square root time dependence, during the first microsecond after the change of power dissipation.