In CMOS technology for EEPROM, refractory metal silicide is currently used to shunt the doped polysilicon layer for the floating gate electrode. Due to their manufacturability, tungsten silicide (WSi2) and tantalum silicide (TaSi2) are widely used in integrated circuit manufacturing. In this paper, electrical tests are performed on MOS capacitors and on memory cells. We will compare three types of silicides: TaSi2 deposited by sputtering and WSi2 deposited with two chemistries: the monosilane reduction of tungsten hexafluoride (MS) and the dichlorosilane reduction of tungsten hexafluoride (DCS). Regarding the cycling performance of the memory cell, tantalumsilicide and tungsten silicide DCS are both good candidates for gate material, but in term of data retention results, they are not the best candidates because of their higher charge loss during bake.
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