A method of forming a heterojunction bipolar transistor device is disclosed. A platform for supporting a vehicle seat and crash test dummy is slidably supported on the primary sled. The polystyrene beads are pre-expanded with the topically applied brominated compounds and a molded pattern is formed from the pre-expanded polystyrene beads. The energy delivery device includes at least one electrode with a tissue penetrating distal end and is configured to be advanced from the interior into a target tissue site to define an ablation volume.