Many applications, such as high-resolution radar or high-speed wireless communications, will profit from the development of low-cost solutions for mm- and sub-mm wave antennas and front-ends. In this work, a wideband integrated silicon lens antenna fed by a quartz leaky-wave cavity is presented, covering the full H-band 220-320GHz). Thanks to a low-loss novel chip interconnect, based on spray coating of low dielectric permittivity materials, the use of waveguide split-blocks is avoided, reaching a wideband, low-loss and cost-effective solution.