This article presents the systematic analysis, modeling, fabrication and demonstration of a passive terahertz imaging detector based on low-NEP 130 nm SiGe HBT technology. The detector includes two independent polarization paths with a single dual-polarization lens-coupled on-chip antenna. Performance is close to optimum with deembedded equivalent noise bandwidth of 512 GHz centered at about 430 GHz. NEP performance of 2.3–23 pW/ √Hz (forward-active) and 4.3–45 pW/ √Hz (saturation) was measured across 200-1000 GHz, and 1 Hz defined NETD of 0.64K in dual channel operation was measured indicating near-zero noise correlation between polarization paths.