Certain embodiments of the invention provide network interface devices, as well as systems and methods for using them. The systems and methods involve detecting the occurrence of electrical events within the patient’s heart by inserting and positioning an implantable lead having an electrode near a cardiac wall as well as detecting mechanical events within the patient’s heart by then inserting and positioning a cardiac motion sensor unit through the inner lumen of the implantable lead. An implantation process occurs in the fins through the epitaxial doped layer to change the crystal lattice of the fins to form amorphized fins. A gate structure carried on a top surface of the device layer operates as a hard mask during the ion implantations to assist in defining a lateral boundary for the hyper-abrupt p-n junction.