【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.更多还原

【Abstract】 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 9×1011 cm-2 and 2×1011 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.更多还原