An ion implantation system including an ion source for generating an ion beam, an end station for holding a substrate to be implanted by the ion beam, and a linear accelerator disposed between the ion source and the end station and adapted to accelerate the ion beam, the linear accelerator comprising at least one acceleration stage including a resonator coil coupled to a drift tube assembly, the drift tube assembly including a first drift tube coupled to a first end of a first insulting rod via interference fit, a second drift tube coupled to a first end of a second insulting rod via interference fit, and a mounting bracket coupled to a second end of the first insulting rod and to a second end of the second insulting rod via interference fit.