Application of spallation neutron sources in support of radiation hardness studies

High-power spallation neutron sources offer a unique opportunity to gather critical measurements on the very early transient displacement damage in semiconductors. This paper discusses the important attributes of spallation neutron facilities used for investigating the transient radiation hardness of semiconductors. By comparing the attributes of some different types of radiation facilities currently used for semiconductor damage characterization, a new and important role for spallation neutron sources is identified. Comparisons are made between the attributes of the spallation neutron source and fast-burst reactors, water-moderated reactors, ion microbeams, and electron accelerators. By incorporating electromagnetic shielding, photocurrent shunts and new experimental techniques, testing at spallation neutron sources has permitted the earliest measurements of transient gain to be lowered from the previous time of 250 μs, achieved at fast-burst reactors, to 8 μs. This is over a factor of 30 improvement in the test capability.