Dependence of electron channel mobility on Si-SiO/sub 2/ interface microroughness
Dependence of electron channel mobility on Si-SiO/sub 2/ interface microroughness
复制标题
电子通道迁移率对 Si-SiO/sub 2/ 界面微观粗糙度的依赖性
DOI：
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发表时间：
1991
影响因子：
4.9
通讯作者：
M. Miyashita
中科院分区：
文献类型：
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作者：
T. Ohmi;K. Kotani;A. Teramoto;M. Miyashita
研究了Si-SiO/Sub2/界面微粗糙度对n-MOSFET电子沟道迁移率的影响。在RCA清洗过程中，通过改变NH/sub4/OH-H/sub2/O/sub2/-H/sub2/O溶液中NH/sub4/OH的混合比例来控制表面微观粗糙度。在评估了MOS晶体管的电学特性之后，对栅氧化层进行了刻蚀，用扫描隧道显微镜(STM)测量了Si-SiO/Sub2/界面的微观粗糙度。随着界面微粗糙度的增加，可由MOSFET的电流-电压特性得到的电子沟道迁移率变小。当界面平均粗糙度为0.2 nm，衬底杂质浓度为4.5×10/sup17/cm/sup-3/时，沟道迁移率约为360 cm/sup2//V-S，即电子体迁移率为400 cm/sup2//V-S。当界面微观粗糙度超过1 nm时，表面粗糙度降至100 cm/sup~2//V-S。
The effect of the Si-SiO/sub 2/ interface microroughness on the electron channel mobility of n-MOSFETs was investigated. The surface microroughness was controlled by changing the mixing ratio of NH/sub 4/OH in the NH/sub 4/OH-H/sub 2/O/sub 2/-H/sub 2/O solution in the RCA cleaning procedure. The gate oxide was etched, following the evaluation of the electrical characteristics of MOS transistors, to measure the microroughness of the Si-SiO/sub 2/ interface with scanning tunneling microscopy (STM). As the interface microroughness increases, the electron channel mobility, which can be obtained from the current-voltage characteristics of the MOSFET, gets lower. The channel mobility is around 360 cm/sup 2//V-s when the average interface microroughness is 0.2 nm, where the substrate impurity concentration is 4.5*10/sup 17/ cm/sup -3/, i.e. the electron bulk mobility is 400 cm/sup 2//V-s. It goes down to 100 cm/sup 2//V-s when the interface microroughness exceeds 1 nm.<<ETX>>