Arrays of resonant tunnelling diodes defined by in-situ focused ion beam lithography: potential millimetre wave/microwave power sources?

The ability to fabricate and electrically contact an array of small, high current density resonant tunnelling diodes (RTDs) with a common bias connection has potential impact in realising solid state millimetre wave/microwave power sources. In this paper, a novel technique is proposed and demonstrated to form these arrays using a combination of in-situ focused ion beam lithography (FIB) with molecular beam epitaxy (MBE) regrowth. Room temperature DC I-V characteristics of the resulting planar devices are presented, together with preliminary s-parameter measurements and power emission spectra of individual FIB RTDs.