Showing papers on "Diode published in 1980"

Evidence for tunneling in reverse‐biased III‐V photodetector diodes

Abstract: Photodiodes made from III‐V group semiconductor alloys have been found to exhibit anomalously high dark currents. We present evidence that tunneling is the dominant source of dark current in many cases. The tunneling current becomes substantial at peak junction electric fields as low as 105 V/cm due to the small direct energy gaps and small effective masses of the materials tested. Tunneling sets limits on the magnitude of the electric field attainable in these materials, and therefore has serious implications on photodetector design and performance.

Temperature dependence of threshold current for quantum‐well AlxGa1−xAs‐GaAs heterostructure laser diodes

Abstract: Data are presented showing that the threshold current density Jth(T) of quantum‐well AlxGa1−xAs‐GaAs heterostructure laser diodes, grown by MO‐CVD, is less temperature dependent than that of conventional DH lasers. T0 in the usual expression Jth∝exp(T/T0) can be high as 437 °C. This behavior is explained in terms of the steplike density of states and the disturbed electron and phonon distribution functions of the quantum‐well active region.

Semiconductor diode laser array

Abstract: An integrated laser array is disclosed in which a plurality of semiconductor lasers are integrated on a semiconductor multi-layer crystal that includes an active layer in which the band gap energy varies in one direction By means of this arrangement a plurality of semiconductor lasers, which differ in their respective oscillating wavelengths over a relatively broad range, can be formed on a common substrate

Manufacture of semiconductor device

Abstract: PROBLEM TO BE SOLVED: To enable efficient manufacturing of a light-emitting diode and provide stable die bonding strength and ohmic contact. SOLUTION: Conductive solder materials 13 and 14 having different melting points are provided on opposite surfaces of a silicon substrate 12. The silicon substrate 12 is set on a stem 11 via the solder material 13 having a high melting point, and a light-emitting diode element 15 is set via the other solder material 14 having a low melting point on the silicon substrate 12. While the stem 11 is heated by a heater, the light-emitting diode 15 is pressed to the stem 11. Since the solder material 13 in contact with the stem 11 has a high melting point, it is melted substantially at the same time as the other solder material 14 having a low melting point so that the stem 11 and the silicon substrate 12 are die-bonded to form eutectic junction, and at the same time, the silicon substrate 12 and a semiconductor element are die-bonded to form an eutectic junction.

New InGaAs/InP avalanche photodiode structure for the 1-1.6 µm wavelength region

Abstract: Low dark current and low multiplication noise properties for an In 0.53 Ga 0.47 As/InP avalanche photodiode are described. The diode is prepared with an In 0.53 Ga 0.47 As light absorption layer and an InP avalanche multiplication region. The lowest dark current density of 5.2 \times 10^{-4} A/cm2is obtained at 90 percent of a breakdown voltage. Multiplication noise power is proportional to the 2.7th power of the current multiplication factor. Impact ionization coefficient by holes is larger by 2-3 times than that by electrons in

1/f Noise in (Hg, Cd)Te photodiodes

Abstract: In this article we present results of experiments to characterize 1/ f noise in Hg 0.7 Cd 0.3 Te n+-on-p junction photodiodes. Under zero-bias voltage conditions, the photodiodes display no 1/ f noise, even in the presence of large photocurrents. Under reverse-bias voltage operation, 1/ f noise is observed. In these experiments, the 1/ f noise was measured as a function of temperature, diode bias voltage, and photon flux. Since these parameters varied the relative contributions of the various current mechanisms, the diode current mechanism responsible for 1/ f noise was isolated. It was found that 1/ f noise is independent of photocurrent and diffusion current but is linearly related to surface generation current. It is proposed that 1/ f noise in reverse-biased (Hg, Cd)Te photodiodes is a result of modulation of the surface generation current by fluctuations in the surface potential.

Differential sample-and-hold circuit

Abstract: A high-speed sample-and-hold circuit well suited for fabrication in monolithic form, the circuit including a pair of capacitors used to track a differential analog signal, and at least two switches for connecting the analog signal to the capacitors in a tracking mode, and for isolating the capacitors from the analog signal in a hold mode. In a preferred embodiment of the invention, the switches are diodes and each capacitor is driven differentially through a separate pair of diodes, which are forward-biased in the tracking mode and reverse-biased in the hold mode. Additional circuitry is provided to compensate for variations in characteristics of the diodes due to temperature changes. Furthermore, the effects of capacitive coupling through the diodes in the hold mode are minimized by disconnecting the analog input signal and substituting a signal derived from the held signal stored in the capacitors.

Electronic Modulated Beam-Steerable Silicon Waveguide Array Antenna

Abstract: The design and experimental findings for a low-cost easily fabricated millimeter-wave line scanner is described. This antenna consists of a 1-mm x 1-mm silicon dielectric rod with a metal grating (periodic structure) on the upper surface and p-i-n diodes mounted on the sidewall. A narrow 8/spl deg/ beam is radiated from the grated (perturbed) surface at an angle dependent on the guide and perturbation spacing. The beam angle is switched over a 10/spl deg/ angle by application of a dc forward current through the p-i-n diode modulators.

Tunneling Current in InGaAs and Optimum Design for InGaAs/InP Avalanche Photodiode

Abstract: Breakdown voltage and dark current density in p+n and n+p In0.53Ga0.47As diodes are compared with theoretical values taking the backward tunneling current into account. Predominant origin of dark current in an InGaAs diode is attributed to the tunneling current. Using these results, optimum design of an InGaAs/InP avalanche photodiode (APD) to obtain low dark current, high multiplication gain, high quantum efficiency and fast response is also discussed.

Fluid cooled solar powered photovoltaic cell

Abstract: Concentrated sunlight impinges on a large area photovoltaic device which is bonded to a highly pliable and thermally and electrically conductive structured copper strain relieving member; the lower face of the structured copper is sealed to a fluid cooled metal heat sink. Large power densities of sunlight are absorbed without appreciable temperature rise. The structured copper accommodates to the difference in expansion between the metal heat sink and the semiconductor wafer. Three embodiments utilize a single planar junction diode, an interdigitated diode, and series connected isolated junction diodes.

Properties of ion-implanted junctions in mercury—cadmium—telluride

Abstract: The formation of n-p junctions by ion-implantation in Hg 0.71 Cd 0.29 Te is shown to be a result of implantation damage. n-p photodiodes have been made by implantation of Ar, B, Al, and P in a p-type substrate with acceptor concentration of 4 × 1016cm-3. The implanted n-type layer is characterized by sheet electron concentration of 1014to 1015cm-2and electron mobility higher than 103cm2. V-1. s-1, for ion doses in the range 1013-5 × 1014cm-2. The photodiodes have a spectral cutoff of 5.2 µm, quantum efficiency higher than 80 percent, and differential resistance by area product above 2000 Ω . cm2at 77 K. The temperature dependence of the differential resistance is discussed. The junction capacitance dependence on reverse voltage fits a linearly graded junction model. Reverse current characteristics at 77 K have been investigated using gate-controlled diodes. The results suggest that reverse breakdown is dominated by interband tunneling in field-induced junctions at the surface, for both polarities of surface potential.

Semiconductor integrated circuit device providing a protection circuit

Abstract: A protective semiconductor integrated circuit device for protecting an internal circuit against an excessively high voltage has a first resistor of a low value resistance interposed between an input terminal and an input gate of the internal circuit. One of the drain and source regions of an MIS type transistor is connected to the input gate of the internal circuit to be protected and the other region of the source and drain is grounded. A capacitor is interposed between the gate of the MIS transistor and the input terminal. A second resistor or a diode of reverse polarity is interposed between the gate of the MIS transistor and ground. The protective device may be fabricated using, a bulk silicon, an insulating substrate such as sapphire, spinel or semi-insulating material, simultaneously with the internal circuit and without changing processes for fabrication of the internal circuit and without requiring any additional masking steps.

Interfacial layer theory of the Schottky barrier diodes

Abstract: The interfacial layer theory considering the surface fixed charge and the voltage drop across the interfacial layer is developed for the Schottky barrier diodes fabricated on the n‐type semiconductor substrate. It is shown that the positive surface fixed charge will reduce the barrier height and then increases the reverse current; the voltage drop across the interfacial layer will increase the ideality factor of the forward biased I‐V characteristic and the voltage dependence of the reverse‐biased I‐V characteristic, aside from the effects of the image force lowering; the fluctuations of the experimental data deduced from the fabricated Schottky barrier diodes with different fabricating conditions are mainly due to the variations of the interfacial‐layer properties such as the interfacial‐layer thickness, the interface states, the surface fixed charges.

Broadband frequency multiplication by multitransition operation of step recovery diode

Abstract: A frequency multiplier which employs a step recovery diode operated in a double pulse mode for each period of the cycle of the input frequency signal provides efficient and high order harmonic generation. The bias circuitry for the diode and impedance characteristics of the input and output bandpass filters are selected to provide stable operation.

Capacitance studies on amorphous silicon Schottky barrier diodes

Abstract: The capacitance C of Schottky barrier diodes prepared by the deposition of Pt onto undoped and phosphorus doped a-Si:H films is studied as a function of frequency f, temperature T and applied voltage V. With increasing f and decreasing T the capacitance decreases by factors as large as 10 indicating that the space charge is located in deep gap states with response times which in part are greater than 103s. The behaviour of Schottky barriers in undoped a-Si:H can well be described in terms of a model with an energy independent density of states close to 1017cm−3eV−1. Doping with PH3 results in an increase of C, accompanied by a decrease in barrier width and barrier height. Fot T > 300 K and V > 0.3 V a strong increase of C is observed which is tentatively attributed to the contribution of interface states.

Integrated solar cells and shunting diodes

Abstract: A method of connecting a shunting diode in parallel with a solar cell for the purpose of improving the tolerance of an array of solar cells to mismatch in cell output, whether caused by physical differences in the cells, cell breakage, or the effect of shading, is disclosed. Also disclosed is a method of forming a plurality of interconnected solar cells on a single sheet of semiconductor material, wherein if required, each cell in the array of cells may be shunted by a diode.

Charge-transfer switched-capacity filter

Abstract: A switched capacity filter having capacities formed by MOS technology on a semiconductor substrate. The connection between two capacities whose first plates are formed by the semiconductor substrate are periodically connected by providing transfer of charges in the substrate on which these two capacities are integrated. The external or other plate of each capacity receives, the input voltage, or a reference voltage, or the surface potential under another capacity which is provided by a reinjection and reading device formed from a diode and a voltage follower stage.

Evidence of space-charge-limited current in amorphous silicon Schottky diodes

Abstract: Palladium/amorphous silicon (a-SiH x ) Schottky barrier diodes have been found to exhibit superlinear dark forward current-voltage (I-V) characteristics over the temperature range 30 to 130°C. The results are consistent with expected behavior for space-charge-limited current in the presence of distributed traps. The trap parameters are deduced from I-V data.

Diffusion length determination in p‐n junction diodes and solar cells

Abstract: An experimental technique for determining the minority carrier diffusion length in the base region of Si p‐n junction diodes and solar cells is described. The procedure is to operate the device in the photoconductive mode and to measure its photoresponse in the wavelength region near the energy gap. The ratio of incident light intensity to photocurrent is a linear function of reciprocal absorption coefficient for each wavelength; the slope of the set of points directly yields the diffusion length. In addition, a nonlinear least‐squares analysis is also used to determine the diffusion length.

Arc annealing of BF + 2 implanted silicon by a short pulse flash lamp

Abstract: Step‐junction diodes are obtained from BF+2 implanted silicon irradiated by a single pulse of light from a flash lamp. The FWHM is 100 μs with energy densities ranging from 12.4 to 20.6 J/cm2. The sheet resistance and the I‐V characteristic have been used to confirm the annealing process.

Semiconductor Devices and Integrated Electronics

Abstract: 1 Semiconductor Junctions and Diodes.- 1.1 Introductory Semiconductor Equations and Concepts.- 1.2 PN Junction Forward Characteristics.- 1.3 Diode Reverse Characteristics.- 1.4 Junction Transient Characteristics.- 1.5 Rectifier Circuits.- 1.6 Zener Reference Diodes.- 1.7 Diodes with Negative Resistance.- 1.8 Electron Beam Bombarded Semiconductor Diodes as Amplifiers.- 1.9 Questions.- 1.10 References and Further Reading Suggestions.- 2 Metal-Semiconductor Schottky-Barrier Diodes.- 2.1 Elementary Metal-Semiconductor Junction Concepts.- 2.2 Barrier Height Measurements.- 2.3 Schottky Barrier Current-Voltage Characteristics.- 2.4 Minority Charge in Schottky Junctions.- 2.5 Schottky Barriers in Integrated Circuits.- 2.6 High Power Schottky Barrier Rectifiers.- 2.7 Questions.- 2.8 References and Further Reading Suggestions.- 3 Microwave Applications of Diodes, Varactors and Tunnel Diodes.- 3.1 Detectors, Mixer Diodes and Related Devices.- 3.2 PIN Diodes as Attenuators and Switches.- 3.3 Varactor Diodes and Parametric Frequency Multiplication and Amplification.- 3.4 Tunnel Diodes and Applications.- 3.5 Questions.- 3.6 References and Further Reading Suggestions.- 4 Bipolar Junction Transistors.- 4.1 General Characteristics.- 4.2 Voltage Rating and Second Breakdown.- 4.3 Factors Controlling the Current Gain.- 4.4 Frequency Performance and Microwave Transistors.- 4.5 Power Transistors.- 4.6 Switching of Bipolar Transistors.- 4.7 Lateral Transistors.- 4.8 Heterojunction Transistors.- 4.9 Questions.- 4.10 References and Further Reading Suggestions.- 5 Thyristors - Controlled PNPN and Related Switch Devices.- 5.1 Basic Concepts of PNPN Structures.- 5.2 Thyristor Turn-on, Turn-off and Power Considerations.- 5.3 Triacs and Other Multilayer Structures.- 5.4 Computer Aided Design Model for a Thyristor Circuit.- 5.5 Thyristor Applications (Brief Comments).- 5.6 Questions.- 5.7 References and Further Reading Suggestions.- 6 JFETs and MESFETs - Field Effect Transistors.- 6.1 Si FET Modeling Including Saturation Velocity Effects.- 6.2 GaAs MESFET Modeling.- 6.3 Dual Gate MESFETs.- 6.4 Microwave Field Effect Transistors.- 6.5 Some Applications of JFETs and MESFETs.- 6.6 Questions.- 6.7 References and Further Reading Suggestions.- 7 Insulated Gate-Field-Effect-Transistors: MOSFETs, IGFETs and Related Devices.- 7.1 Introduction.- 7.2 First-Order Theory of a MOSFET.- 7.3 Further Consideration of MOSFET Characteristics.- 7.4 MOSFET Saturation Models.- 7.5 The Transition from IGFET to Bipolar Transistor Performance.- 7.6 Semiconductor-Insulator and Insulator-Metal Interfaces.- 7.7 Fabrication Processes for IGFETs.- 7.8 CMOS Structures and Logic.- 7.9 Computer Aided Design of MOSFET Circuits for Large Scale Integration.- 7.10 MOSFET Switches.- 7.11 Noise in MOSFETs.- 7.12 Special Purpose MOSFETs.- 7.13 Questions.- 7.14 References and Further Reading Suggestions.- 8 Integrated Circuit Fundamentals.- 8.1 Large Scale Integration.- 8.2 Yield: The Designer'1 Semiconductor Junctions and Diodes.- 1.1 Introductory Semiconductor Equations and Concepts.- 1.2 PN Junction Forward Characteristics.- 1.3 Diode Reverse Characteristics.- 1.4 Junction Transient Characteristics.- 1.5 Rectifier Circuits.- 1.6 Zener Reference Diodes.- 1.7 Diodes with Negative Resistance.- 1.8 Electron Beam Bombarded Semiconductor Diodes as Amplifiers.- 1.9 Questions.- 1.10 References and Further Reading Suggestions.- 2 Metal-Semiconductor Schottky-Barrier Diodes.- 2.1 Elementary Metal-Semiconductor Junction Concepts.- 2.2 Barrier Height Measurements.- 2.3 Schottky Barrier Current-Voltage Characteristics.- 2.4 Minority Charge in Schottky Junctions.- 2.5 Schottky Barriers in Integrated Circuits.- 2.6 High Power Schottky Barrier Rectifiers.- 2.7 Questions.- 2.8 References and Further Reading Suggestions.- 3 Microwave Applications of Diodes, Varactors and Tunnel Diodes.- 3.1 Detectors, Mixer Diodes and Related Devices.- 3.2 PIN Diodes as Attenuators and Switches.- 3.3 Varactor Diodes and Parametric Frequency Multiplication and Amplification.- 3.4 Tunnel Diodes and Applications.- 3.5 Questions.- 3.6 References and Further Reading Suggestions.- 4 Bipolar Junction Transistors.- 4.1 General Characteristics.- 4.2 Voltage Rating and Second Breakdown.- 4.3 Factors Controlling the Current Gain.- 4.4 Frequency Performance and Microwave Transistors.- 4.5 Power Transistors.- 4.6 Switching of Bipolar Transistors.- 4.7 Lateral Transistors.- 4.8 Heterojunction Transistors.- 4.9 Questions.- 4.10 References and Further Reading Suggestions.- 5 Thyristors - Controlled PNPN and Related Switch Devices.- 5.1 Basic Concepts of PNPN Structures.- 5.2 Thyristor Turn-on, Turn-off and Power Considerations.- 5.3 Triacs and Other Multilayer Structures.- 5.4 Computer Aided Design Model for a Thyristor Circuit.- 5.5 Thyristor Applications (Brief Comments).- 5.6 Questions.- 5.7 References and Further Reading Suggestions.- 6 JFETs and MESFETs - Field Effect Transistors.- 6.1 Si FET Modeling Including Saturation Velocity Effects.- 6.2 GaAs MESFET Modeling.- 6.3 Dual Gate MESFETs.- 6.4 Microwave Field Effect Transistors.- 6.5 Some Applications of JFETs and MESFETs.- 6.6 Questions.- 6.7 References and Further Reading Suggestions.- 7 Insulated Gate-Field-Effect-Transistors: MOSFETs, IGFETs and Related Devices.- 7.1 Introduction.- 7.2 First-Order Theory of a MOSFET.- 7.3 Further Consideration of MOSFET Characteristics.- 7.4 MOSFET Saturation Models.- 7.5 The Transition from IGFET to Bipolar Transistor Performance.- 7.6 Semiconductor-Insulator and Insulator-Metal Interfaces.- 7.7 Fabrication Processes for IGFETs.- 7.8 CMOS Structures and Logic.- 7.9 Computer Aided Design of MOSFET Circuits for Large Scale Integration.- 7.10 MOSFET Switches.- 7.11 Noise in MOSFETs.- 7.12 Special Purpose MOSFETs.- 7.13 Questions.- 7.14 References and Further Reading Suggestions.- 8 Integrated Circuit Fundamentals.- 8.1 Large Scale Integration.- 8.2 Yield: The Designer's Dilemma.- 8.3 Bipolar IC Technology.- 8.4 MOS Inverters.- 8.5 MOS Logic Circuits and Scaling.- 8.6 Future Limits in Digital Electronics.- 8.7 Questions.- 8.8 References and Further Reading Suggestions.- 9 Integrated Circuit Applications.- 9.1 Linear Integrated Circuits.- 9.2 Communications Applications.- 9.3 Applications in Watches, Cameras and Automobiles.- 9.4 Semiconductor Memories.- 9.5 Microprocessors.- 9.6 Small Calculators.- 9.7 Questions.- 9.8 References and Further Reading Suggestions.- 10 Charge-Transfer Devices.- 10.1 General Concepts.- 10.2 Loss Mechanisms in CCDs.- 10.3 Charge-Coupled Delay Lines and Filters.- 10.4 Charge-Coupled Memories.- 10.5 Imaging CCD Arrays.- 10.6 CCD Logic Structures.- 10.7 Bucket-Brigade Circuits.- 10.8 Questions.- 10.9 References and Further Reading Suggestions.- 11 Avalanche-Diode Microwave Oscillators, Amplifiers, and Gunn Devices.- 11.1 Introduction.- 11.2 Read Diode Oscillator Concepts.- 11.3 Impatt Performance.- 11.4 Trapatt Oscillations.- 11.5 Avalanche-Diode Amplifiers.- 11.6 Comments on Performance.- 11.7 Transferred-Electron Device (Gunn) Oscillatros.- 11.8 TED (Gunn) Logic Concepts.- 11.9 Questions.- 11.10 References and Further Reading Suggestions.- 12 Solar Cells.- 12.1 Solar Energy.- 12.2 Silicon Solar Cells.- 12.3 Solar Cells of GaAs, InP, and Related Semiconductors.- 12.4 Cells of CdS and Related Semiconductors.- 12.5 Discussion.- 12.6 Questions.- 12.7 References and Further Reading Suggestions.- 13 Light Detecting Semiconductor Devices.- 13.1 Photodiodes.- 13.2 Detectivity.- 13.3 Photoconductive Detectors.- 13.4 Phototransistors.- 13.5 Photocathodes and Negative-Electron-Affinity-Emitting Devices.- 13.6 Vidicon Camera Tubes and Silicon Diode Array Targets.- 13.7 Electrophotographic Copying.- 13.8 Questions.- 13.9 References and Further Reading Suggestions.- 14 Light Emitting Diodes and Injection Lasers.- 14.1 Light Emission from Direct-Gap GaAs1?xPx.- 14.2 Radiative and Nonradiative Recombination in GaAs Diodes.- 14.3 GaP Light-Emitting Diodes.- 14.4 Other Light-Emitting Materials.- 14.5 Applications of Light-Emitting Diodes.- 14.6 Heterojunction A1xGa1?xAs - GaAs Injection Lasers.- 14.7 Other Injection Lasers.- 14.8 Injection Lasers and LEDs as Light Sources for Optical Communications Systems.- 14.9 Questions.- 14.10 References and Further Reading Suggestions.- 15 Semiconductor Sensors and Transducers.- 15.1 Semiconductor Sensors Involving Magnetics.- 15.2 Strain Sensors and Related Transducers.- 15.3 Temperature Sensors.- 15.4 Gas Sensing Semiconductor Structures.- 15.5 High-Energy Particle and Gamma Ray Sensors.- 15.6 Questions.- 15.7 References and Further Reading Suggestions.- Book List.

Modular radiation detector array and module

Abstract: A modular radiation detector array which allows improved spatial resolution and facilitates installation and replacement for repair. Each module includes two detachably assembled portions with one portion including a plurality of spaced plates for collimating radiation. The second portion includes a printed circuit board, a semiconductor diode array chip mounted on the printed circuit board, and a plurality of scintillator crystals mounted on the semiconductor chip with each crystal overlying a diode. Signals from the diodes are applied to signal processing means by a cable which is readily connected to and disconnected from the diode array.

Antennas and waveguides for far-infrared integrated circuits

Abstract: Antennas and waveguides for the wavelength range 0.1-3 mm are considered. Emphasis is placed on those designs which lend themselves to integration with each other and with other components such as diodes. The general properties of FIR antennas are reviewed. A novel silicon waveguide antenna is discussed, and its design, simulation, fabrication, and performance at 119 μm are described. This antenna has a highly symmetrical, single-lobed beam with 3 dB beamwidths of 35 and 38° in the E - and H -planes, respectively. The gain (measured in microwave simulation) is 12.8 dB. This antenna is well suited for integration with Schottky diodes. The related subject of FIR waveguides is discussed. Experiments with metal transmission lines at 119 μm are described and dielectric guides related to the waveguide antenna are also considered. Using components such as these it may soon be possible to construct receiver front ends for this wavelength range in integrated-circuit form.

I‐V and C‐V characteristics of Au/TiO2 Schottky diodes

Abstract: The electrical characteristics of Au/n‐TiO2 Schottky diodes have been studied using I‐V and C‐V measurements. TiO2 samples with working face perpendicular to the c axis are reduced in a vacuum of 10−6 Torr at 800 °C for about 5 h and then quenched. The resistivities are in the range 20–30 Ω cm. The barrier heights deduced from I‐V characteristics in agreement with the thermionic emission theory are in the range 0.87–0.94 eV. C‐V data yield lower barrier heights and show a frequency dependence attributed to relaxation phenomena occurring in a disturbed layer near the surface. Comparison with results relative to Au/n‐SrTiO3 diodes shows that the barrier heights obey the Schottky model for these ionic semiconductors, confirming the role of the electron affinity in the band bending formation.

Flash x-ray tube for diffraction studies on a two-stage light-gas gun

Abstract: A flash x‐ray tube has been fabricated and has been driven by a Blumlein pulse generator to peak voltages of 60 to 80 kV and peak anode currents of 8 to 10 kA The pulse width, dependent upon the anode‐cathode spacing, can be made ∼80‐ns wide, and a small spot or line focus is possible These features make the device useful for flash x‐ray diffraction studies Current in the diode region exceeds the calculated space‐charge limited values, probably because of neutralization of charge by plasma ejected from the cathode during the initial phase of the discharge

Ion-implanted low-barrier PtSi Schottky-barrier diodes

Abstract: An ion-implanted, shallow n+layer has been used for lowering the barrier height of PtSi-n-Si Schottky diodes. Barrier height reductions up to 200 mV have been achieved with little degradation of the diode's reverse-current characteristics. During silicide formation, the implanted ions are "pushed" ahead of the PtSi-Si reaction zone and pile up at the silicide-silicon interface, resulting in more barrier lowering than would be expected from the ion-implant dose. A model including the impurity pileup is presented and calculations based on the model are shown to be in reasonable agreement with experimental measurements.

Design of Loaded-Line p-i-n Diode Phase Shifter Circuits

Abstract: The design of three types of loaded-line p-i-n diode digital phase shifter circuits is presented. The three configurations considered are 1) main line mounted, 2) stub mounted, and 3) switchable stub length. Expressions for various design parameters are derived. Calculations show that for the 22.5/spl deg/ phase bit the maximum bandwidths for three circuits are 22.7, 19.2, and 18.4 percent, respectively. Starting from the p-i-n diode parameters, optimum designs of these circuits for obtaining minimum insertion loss, maximum bandwith, and minimum size are also discussed. It is found that the switchable stub length type configuration is suitable when nearly ideal p-i-n diodes are used while stub mounted type configuration is suitable for nonideal diodes. Experimental and theoretical performance (bandwidth and insertion loss) of stub mounted type circuits are compared and found to be in good agreement.

Optimization of oxide-semiconductor/base-semiconductor solar cells

Abstract: In order to get the maximum output from oxide-semiconductor/base-semiconductor solar cell, one has to incorporate an ultrathin insulating layer so that the resulting configuration is a semiconductor-insulator-semiconductor (SIS) diode. The performance of such SIS diodes is equivalent to a metal-insulator-semiconductor (MIS) solar cell. The key parameters in the optimization are the thickness of the insulating layer and the work function of the oxide semiconductor. Using the existing knowledge of the parameters for a number of oxide semiconductors one would conclude that ITO, ZnO, and SnO 2 are good oxides for the fabrication of SIS solar cells. Some properties of highly conducting and highly transparent ZnO films which have been fabricated in our laboratory are presented. These results suggest that these ZnO films should be useful for fabricating low-cost SIS solar cells.