Development of aluminum cone tip for fast ignition target

We have developed a novel method to fabricate an aluminum cone tip to attach the conventional gold cone for fast ignition. An aluminum cone tip is fabricated by laser thermal chemical vapor deposition. Trimethylaluminum (TMA) is used as a chemical precursor of aluminum. TMA is introduced into a vacuum chamber with argon gas and heated on a substrate by using a heater and a laser. Aluminum products are measured by using digital zoom microscope. It is found that the deposition rate is increased with the increase of the substrate temperature, argon gas flow, and the laser intensity. However, the increase of the laser intensity increases the temperature of the deposit, and also causes the melt of the deposit. Under suitable conditions, we succeeded in making desired aluminum conical shape with 32 mu m height, whose size is difficult by conventional cutting technology. Therefore, this method will be important not only to the fusion experiments but also to many other industrial applications.