Effect of a body-tie structure fabricated by partial trench isolation on the suppression of floating body effect induced soft errors in SOI SRAM investigated using nuclear probes

摘要

Soft errors induced by proton, helium and oxygen ion irradiations were measured as a function of distance between a body electrode under partial trench isolation and a metal pad connected to a tungsten via for the first metal layer of a silicon-on-insulator (SOI) static random access memory. Abnormal drain charges induced by ion irradiations with various distances in the SOI metal oxide semiconductor field effect transistor were simulated to be compared with the experimental results. The soft errors were found to depend on the distance between the body electrode and the metal pad in the case of the abnormal drain charge, which is induced by incident ions, lower than the critical charge of the SRAM cells. The soft errors did not depend on the distance for the abnormal drain charges higher than the critical charge.