Ahmed Hassona1, Zhongxia Simon He1, Chiara Mariotti2, Franz Dielacher2, Vessen Vassilev1, Yinggang Li3, Joachim Oberhammer4, Herbert Zirath1 1Chalmers University of Technology, Gothenburg, Sweden 2Infineon Technologies Austria AG, Villach, Austria 3Ericsson AB, Gothenburg, Sweden 4KTH Royal Institute of Technology, Stockholm, Sweden Abstract—This paper presents a novel D-band interconnect implemented in a low-cost embedded Wafer Ball Grid Array (eWLB) commercial process. The transition is realized through a patch slot antenna directly radiating to a standard waveguide opening. The interconnect achieves low insertion loss and good bandwidth. The measured minimum Insertion Loss (IL) is 2 dB and the average is 3 dB across a bandwidth of 22% covering the frequency range 110-138 GHz. In addition, the structure is easy to integrate as it does not require any special assembly nor any galvanic contacts. Adopting the low-cost eWLB process and standard waveguides makes the transition an attractive solution for interconnects beyond 100 GHz.