摘要
在等离子体增强化学气相沉积(PECVD)系统中,利用逐层淀积非晶硅(a-Si)和等离子体氧化相结合的方法制备二氧化硅(SiO2)介质层.电容电压(C-V)和电导电压(G-V)测量结果表明:利用该方法在低温(250℃)条件下制备的SiO2介质层均匀致密,其固定氧化物电荷和界面态密度分别为9×1011cm-2和2×1011cm-2.eV-1,击穿场强达4.6MV/cm,与热氧化形成的SiO2介质层的性质相当.将该SiO2介质层作为控制氧化层应用在双势垒纳米硅(nc-Si)浮栅存储结构中,通过调节控制氧化层的厚度,有效阻止栅电极与nc-Si之间的电荷交换,延长存储时间,使存储性能得到明显改善.
The silicon dioxide （SiO2 ） film was fabricated from layer-by-layer depositing amorphous silicon （a-Si） film combined with step-by-step plasma oxidation in the plasma-enhanced chemical vapor deposition （PECVD） system. The capacitance-voltage（ C- V） and conductance-voltage（ G- V） characteristics show that the fixed charge and interface state densities of the SiO2 film are 9 × 10^11 cm^-2 and 2 ×10^11 cm^-2·eV^-1, respectively. Furthermore, the breakdown field strength is as high as 4.6 MV/cm, which is comparable to that formed by hot oxidation. The prepared SiO2 is employed as control oxide in nc-Si based double-barrier floating gate memory structure and is found to be an effective way to prevent the charge exchange between the gate electrode and nc-Si, which also lead to an enhancement in the retention time. The improved performance of the memory is discussed and is ascribe to the moderate-thickness of SiO2 as well as its excellent electrical properties.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第7期4482-4486,共5页
Acta Physica Sinica
基金
国家自然科学基金(批准号:90301009,60571008)
国家重大科学研究计划项目(批准号:2006CB932202)资助的课题~~
关键词
等离子体氧化
二氧化硅
纳米硅
控制氧化层
plasma oxidation, silicon dioxide, nanocrystalline silicon, control oxide
