Superlattice electronic devices as high-performance oscillators between 60–220 GHz

Abstract

Negative differential resistance devices were fabricated from four epitaxial wafers with different GaAs/AlAs superlattices and evaluated in resonant-cap full-height waveguide cavities. These devices generated output powers in the fundamental mode between 62–108 GHz. The best RF powers were 58 mW at 66 GHz, 42 mW at 78 GHz, and 28 mW at 94 GHz. The RF power of 15 mW at 101 GHz constitutes a 30-fold improvement over previous results; the highest fundamental oscillation frequency was 108 GHz. In a second-harmonic mode, one device yielded 2.0 mW at 216 GHz, the highest second-harmonic frequency to date for a GaAs/AlAs superlattice.