基于Sn掺杂Ge_2Sb_2Te_5的相变存储器器件单元存储性能

Storage characteristics of phase change memory cells based on Sn-doped Ge_2Sb_2Te_5

采用0.18μm标准工艺制备出基于Sn掺杂Ge2Sb2Te5相变材料的相变存储器器件单元,利用自行设计搭建的电学测试系统研究了其存储性能。结果表明:Sn的掺杂没有改变Ge2Sb2Te5的相变特性,其相变阈值电压和阈值电流分别为1.6V和25μA;实现了器件单元的非晶态(高阻)与晶态(低阻)之间的可逆相变过程;器件单元中相变材料结晶所需电流最低为1.78mA(电流宽度固定为100ns)、结晶时间大于80ns(电流高度固定为3mA);相变材料非晶化脉冲电流宽度为30ns时,所需电流大于3.3mA;与Ge2Sb2Te5相比,Sn的掺杂降低了SET操作的脉冲电流宽度,提高了结晶速度,有利于提高相变存储器的存储速度。

Phase change memory cells based on Sn-doped Ge2Sb2Te5 has been fabricated in 0.18 μm standard process and the storage characteristics have been investigated using the home-made electrical testing system.The results show that the doping of Sn did not influence the reversible phase change phenomenon in Ge2Sb2Te5.The threshold voltage and threshold current showed in the current-voltage curve are 1.6V and 25uA,respectively.The crystallization programming（SET） shows that the current pulse magnitude should be larger than 1.78mA when current pulse width was fixed on 100ns;while the current pulse width should be longer than 80ns when current pulse magnitude was fixed on 3mA.And the amorphization programming（RESET） will not happen until the current pulse magnitude reaches 3.3mA when the pulse width was fixed on 30ns.