An embodiment is directed to an embolic device comprised of a coil made of a first material and disposed on the inside of a tube structure made of a second material. The tube structure has micro-fabricated fenestrations formed in the tube to provide fluid communication between the lumen of the tube and the surrounding environment, thereby exposing the inner coil. The fenestrations also trip flow around the embolic device. In one embodiment, the embolic device is comprised of a tantalum coil on the inside of a polyetheretherketone (PEEK) tube. The PEEK tube has the advantage of providing a micromachined delivery implant frame and radiopacity, while the internal tantalum coil provides radiopacity and thrombogenicity. A material other than PEEK may be used for embodiments of embolic devices without departing from the spirit of the disclosure.