Photo-conductive lens antennas (PCAs) exploit the ultra-short photoconductivity phenomenon of specific semiconductors in order to generate pulsed radiation in the THz regime. State of the art PCAs suffer from high dispersion and low radiation efficiency over the large generated bandwidth due to the poor coupling between the antenna and the dielectric lens. In this work, a leaky lens PCA is proposed to overcome these issues. The presented structure, indeed, aims at a 1:15 bandwidth (0.1 THz – 1.5 THz). The design, assembly and manufacture of a LT-GaAs membrane-based leaky lens PCA are shown and discussed together with the measurement of the radiated power.@en