【摘要】 制备了几种PLOTOX结构EEPROM存贮管,对其擦写过程作了测试分析.讨论了擦写时存贮管电容分压的物理模型,实验测量通过超薄氧化层的Fowler-Nordheim隧道电流,推导出在擦写过程中浮栅上存贮电荷量的计算公式.研究了存贮管的阈值电压,特别指出它不仅与浮栅上积累电荷有关,而且与测量时的漏电压有关,建立了存贮管阈值电压的计算公式.最后,介绍了实验结果并作讨论,指出有关公式可作为设计EEPROM存贮单元的基础.更多还原

【Abstract】 FLOTOX EEPROM memory transistors with different structures have been fabri-cated.Their erase/write characteristics are examined.A physical model is proposedfor the gate voltage division between the first and second gate capacitances during theerasing or writing operations,the Fowler-Nordheim type tunneling current through thethin oxide is measured and two expressions are derived for calculating the amount ofstorage charge at the floating gate in the erasing or writing process.It is found hatthe threshold voltage in the memory transistor not only depends on the total storagecharge at the floating gate,but also on the drain voltage in the reading process.Basedon this fact,an expression of threshold voltage has been deduced.It is concluded,afterthe comparison of theory with experimental results,that the expressions presented inthis paper can be used as the fundamentals for designing EEPROM memory cells.更多还原