Above X-Band Performance of Baritt Diodes

The predicted small signal noise measure and impedance of pnnp Baritt diodes is described for three values of n region doping density, N_d, at frequencies up to 20GHz. It is shown that for suitable values of N_d, small signal noise measures of order 10dB or less can be maintained up to 20GHz, and small signal negative resistances of at least 1 ohm. A large signal diode simulation is used in conjunction with a simple design approach, to predict the output power of pnnp oscillators at 15GHz. Assuming a diode series loss of 0.3 ohm, an output power of 17 mW is predicted for a diode with N_d = 10¹⁶cm^-3.