Low-Frequency Noise in Si1-xGex p-Channel Metal Oxide Semiconductor Field-Effect Transistors
Low-Frequency Noise in Si1-xGex p-Channel Metal Oxide Semiconductor Field-Effect Transistors
复制标题
Si1-xGex p 沟道金属氧化物半导体场效应晶体管中的低频噪声
DOI：
10.1143/jjap.40.5290
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发表时间：
2001
影响因子：
1.5
通讯作者：
J. Murota
中科院分区：
文献类型：
--
作者：
T. Tsuchiya;T. Matsuura;J. Murota
研究了Si1-xGex p沟道金属氧化物半导体场效应晶体管（pmosfet）在Ge分数x=0.2, 0.5, 0.7和Si1-xGex厚度dSiGe为2-14 nm时的低频噪声（LFN）。虽然Si1-xGex pmosfet的LFN似乎是dSiGe和Ge分数的复杂函数，但结果表明，Si1-xGex pmosfet的LFN可以低于传统Si pmosfet。此外，为了评估Si1-xGex/Si异质结构界面处的陷阱密度，研究了显示最大跨导gmMAX的偏置条件下的噪声功率。在偏置条件下，漏极电流主要在埋藏的Si1-xGex沟道中流动，而不在表面的Si沟道中流动。表面产生电流也被用来评估栅极氧化物和硅盖层之间的界面上的陷阱密度。噪声功率与dSiGe和Ge分数的关系与gmMAX的关系较好，但与表面产生电流的关系不一致。结果表明，gmMAX偏置条件下的噪声特性反映了Si1-xGex/Si异质结构界面处的陷阱密度，与gmMAX行为相符合。
Low-frequency noise (LFN) in Si1-xGex p-channel Metal Oxide Semiconductor Field-Effect Transistors (pMOSFETs) with a relatively wide range of Ge fraction x=0.2, 0.5, 0.7, and Si1-xGex thickness dSiGe of 2–14 nm are investigated. Although LFN of Si1-xGex pMOSFETs seems to be complicated functions of dSiGe and Ge fraction, it is shown that LFN in Si1-xGex pMOSFETs can be lower than that in conventional Si pMOSFETs. Moreover, in order to evaluate the trap density at the Si1-xGex/Si heterostructure interface, the noise power at bias conditions showing the maximum transconductance gmMAX is examined. At the bias conditions, drain current is confirmed to flow mainly in the buried Si1-xGex channel, but not in the surface Si channel. Surface generation current is also examined to evaluate the trap density at the interface between the gate oxide and the Si capping layer. The dependence of the noise power on dSiGe and Ge fraction corresponds well to that of gmMAX, but not to that of the surface generation current. It is concluded that the noise characteristics at the gmMAX bias conditions reflect the trap density at the Si1-xGex/Si heterostructure interface, and correspond well to gmMAX behavior.