This paper presents theoretical calculations of the large-signal admittance and efficiency achievable in a silicon p-n-v-ns Read IMPATT diode. A simplified theory is employed to obtain a starting design. This design is then modified to achieve higher efficiency operation as specific device limitations are reached in large-signal (computer) operation. Self-consistent numerical solutions are obtained for equations describing carrier transport, carrier generation, and space-charge balance. The solutions describe the evolution in time of the diode and its associated resonant circuit. Detailed solutions are presented of the hole and electron concentrations, electric field, and terminal current and voltage at various points in time during a cycle of oscillation. Large-signal values of the diode's negative conductance, susceptance, average voltage, and power-generating efficiency are presented as a function of oscillation amplitude for a fixed average current density. For the structure studied, the largest microwave power-generating efficiency (18 percent at 9.6 GHz) has been obtained at a current density of 200 A/cm2, but efficiencies near 10 percent were obtained over a range of current density from 100 to 1000 A/cm2.

Large-signal analysis of a silicon Read diode oscillator

Equations are presented which fit the experimental dependence of carrier mobilities on doping density and field strength in silicon. The curve-fitting procedures are described.

Carrier mobilities in silicon empirically related to doping and field

This paper reviews the present knowledge of charge transport properties in silicon, with special emphasis on their application in the design of solid-state devices. Therefore, most attention is devoted to experimental findings in the temperature range around 300 K and to high-field properties. Phenomenological expressions are given, when possible, for the most important transport quantities as functions of temperature, field or impurity concentration. The discussion is limited to bulk properties, with only a few comments on surface transport.

A review of some charge transport properties of silicon

The short‐circuit photocurrent from an avalanche photodiode is calculated using an exact solution of the differential transport equations for the multiplication region. The dcelectric field and the hole and electron velocities are assumed constant in the avalanche region into which photoelectrons are injected. It is shown that the electron‐ and hole‐ionization coefficients α and β remain constant over a practical range of multiplied photocurrents. Computer studies of the solution show that avalanche multiplication does not reduce the device bandwidth as long as the dc multiplication M 0 is less than the ratio of α and β, i.e., as long as M0 α/β. The previously unspecified ``effective'' transit time, τ1, in this equation is approximately τ1 = N(β/α)τ, where N is a number varying slowly from ⅓ to 2 as β/α varies from 1 to 10−3, and τ is the multiplication‐region transit time. The complete solution of this problem thus shows that the widely different results previously obtained for β/α = 0 and β/α = 1 are continuously joined, and provides a simple criterion for judging the ranges of validity of the two limiting cases. The results emphasize the practical importance of obtaining the required multiplication at fields such that M 0<α/β where the multiplication does not affect the bandwidth. This also leads to minimum excess avalanche‐region noise, and hence to the closest possible solid‐state analog to the vacuum‐tube photomultiplier.

Avalanche‐Photodiode Frequency Response

Drift velocity of electrons and holes and associated anisotropic effects in silicon

The field-dependence of carrier mobility in silicon and germanium

Using an ab initio, time-dependent calculational method, we study the non-linear dynamics of a two-electron quantum dot in the presence of ultrashort Thz laser pulses. The analysis of the contribution of the various partial waves to two-electron joint radial and energy distribution patterns revealed strongly correlated electron ejection channels. In the double-ionization process, regardless of the photon energy, the two-electron wave packets are born and remain concentrated until the pulse’s peak; at later times, and depending on the photon energy of the field, distinctly different patterns emerge. Our calculations also showed the gradual transition of the radial and energy patterns from a single-peak to a doubly peaked structure, associated with the direct and the sequential double-ionization mechanisms, respectively.

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A.C. Prior

Papers

The field-dependence of carrier mobility in silicon and germanium

Dynamics of Correlated Double-Ionization of Two-Electron Quantum Dots in Laser Fields