Effects of different TMS and TMG flow rate on the content of elements in the fabrication of GDP target

Abstract

Inertial confinement fusion (ICF) is one of the important science domains which are developing quickly in the present world and capsule structure is employed as the thermonuclear reaction fuel container. At present, germanium-doped glow discharge hydrocarbon polymer (GDP) and silicon-doped GDP are chosen as the most common used outer spherical shell of ignition target. The content of doping elements and the amount of Oxygen mixed into the material during preparation are considered to be two of the factors which may influence the results of ICF ignition experiments.In this paper, one set of germanium-doped GDP fabricated by different volume flow rate of tetramethylgermanium (TMG) and another set of silicon-doped GDP fabricated by different volume flow rate of tetramethylsiane (TMS) are used as samples. The element content of the GDP thin film is analyzed by ion beam analysis method. In the work, the ratio of carbon, oxygen and doping elements has been measured. It is found that the content of doping elements (Ge or Si) in the material increases linearly with the flow rate of TMS and TMG. The growth rate of doping elements in Si doped samples is higher than that of Ge doped samples. The content of O in the samples also increased with the increase of TMS/TMG flow rate. This work provides a reference for capsule manufacture technology to fabricate the optimized GDP materials with certain range of concentration of dopants and oxygen for ICF ignition experiments.