Read-Type Varactors for Parametric Amplifier Applications

The use of Read-type HI-LO doping profiles in varactors for pararnetric amplifier applications is shown to result in improved performance over conventional structures. Optimal diode doping Ievels layer thicknesses, and pump drive levels are derived which give specified frequency performance while minimizing pump power requirements, minimizing noise, maximizing dynamic range, and reducing amplifier sensitivity to pump power fluctuations. The optimum device design is based on environmental Iimitations such as pump power, circuit losses and impedance Ievels and the unavoidable diode series resistance level. Design examples are given for 10- and 100-GHZ parametric amplifiers.