Abstract:
The thermal limits of the two-drift impact avalanche and transit-time (IMPATT) diode operating in the pulsed mode in the 8-mm wavelength region with a microwave power as high as 30–35 W have been estimated. It is shown that $p$–$n$ junction overheat at an operating pulse length of 300 ns and a supply current amplitude of 11.3–15 A amounts to 270–430$^\circ$C relative to an ambient medium. The temperature limit of junction overheating, above which IMPATT diodes rapidly degrade, was determined as 350$^\circ$C. The presented results of X-ray phase analysis and depth profiles of Au–Pt–Ti–Pd–Si ohmic contact components confirm thermal limits of the IMPATT diode operating in the pulsed mode.