Internally Integrated Active-Type Patch Antenna for Semiconductor Superlattice THz Oscillators

Semiconductor superlattices are well known to exhibit negative resistance i.e., gain medium like properties at high frequencies. In order to exploit these gain-like properties as an oscillator, one has to compensate very large inductive impedance (Im[Z] ≥ 150 |Re[Z]|). In this paper, we present a novel integrated active-type patch antenna to design the semiconductor superlattice THz oscillators. Within this integrated model, the active source is embedded within a benzocyclobutene dielectric cavity sandwiched between gold metal layers. The metal layer underneath provides THz/DC ground whereas the top metal functions as a radiating antenna simultaneously providing DC bias to the embedded superlattice active source. The design principle is based on satisfying the self-consistent oscillator impedance relationship, along with the efficient radiation of resonating cavity mode. The two oscillator-type active antenna configurations proposed are capable of matching impedance within few ohms of Im[Z] while achieving an antenna gain of >; 5 dBi for a TM₁₀ cavity resonating mode.