This article presents a novel design of a full band E -plane waveguide bend for a direct WR 3.4 waveguide flange-to-chip connection for applications from 220 GHz to 320 GHz. The single layer silicon micromachined design includes a central resonator with input and output matching elements. The design is fabricated by silicon micromachining with sub-micron precision. Measured insertion loss is from 0.08-0.3 dB across the band and better than 0.15 dB across 80% of the band. Measured return loss is better than 14.7 dB and better than 20 dB across 80% of the band.