Student Abstracts: Materials Sciences at PPPL

Burst Strength Testing and Pressure Fatigue Analysis of Silicon Wafers as Hibachi Foil. ABBY OELKER (Lehigh University, Bethlehem, PA 18015) PAUL LAMARCHE (Princeton Plasma Physics Laboratory, Princeton, NJ 08543) .
To enable inertial confinement fusion with krypton fluoride lasers, it is necessary to develop a material boundary that will maximize transmission efficiency of electrons into the laser gas and withstand more than one hundred million electron beam shots. Silicon wafers - chosen for their effectiveness in transmitting electrons and relative ease of manufacture were to be analyzed for burst strength and durability. Burst strength was determined by manual hydrostatic testing. It was found that wafers with one side polished had an average burst strength of 148.57 psi and wafers with both sides polished had an average burst strength of 257.71 psi. The discrepancy in burst strengths for single side and double side polished wafers was attributed to imperfections in the unpolished surfaces of the single side polished wafers. Due to hardware problems and time constraints, no durability (pressure fatigue) testing was completed. Future research will include adapting the wafers for operation in an environment of hydrostatic shock, fluorine, x-rays, ultra violet light, low energy electrons, and hydrofluoric acid.