Fabrication and Characterization of Germanium Channel Schottky Barrier MOSFET

随着半导体技术的不断发展，SiMOSFET器件的小型化日益接近其物理极限，而具有高迁移率的Ge材料和HfO2等高κ介质由于其在未来MOSFET技术中的应用前景得到研究者的广泛关注。各种新结构GeMOSFET器件中，肖特基源漏场效应晶体管（SB-MOSFET）因为在源漏浅结的制造、源漏接触电阻的降低、制备温度的降低和制备工艺的简化等方面具有优势而成为了研究的热点。 本文首先通过仿真模拟分析了SB-MOSFET的特性和工作原理，并分别设计了传统pn结源漏MOSFET和SB-MOSFET两种器件的结构、工艺及版图。分别以体Ge、体Si、绝缘体上Ge材料（germaiumoninsulator,GO...With downscaling of MOSFET to its physical limitation, germanium has been extensively investigated as channel material to replace Si due to its high carrier mobilities. Schottky barrier MOSFET is expected for the competitive MOSFET devices due to its advantages of shallow junction preparation, low resistance contact preparation, low temperature process and process simplification. Ge SB-MOSFETs w...学位：工学硕士院系专业：物理与机电工程学院物理学系_微电子学与固体电子学学号：1982011115287

Schottky Barrier S /D Metal Oxide Semiconductor Field Effect Transistors with Ge /SiGe Heterostructure

制备了氧化铪(HfO2)高k介质栅SI基gE/SIgE异质结构肖特基源漏场效应晶体管(Sb-MOSfET)器件,研究了n型掺杂SI0.16gE0.84层对器件特性的影响,分析了n型掺杂SIgE层降低器件关态电流的机理。使用uHV CVd沉积系统,采用低温gE缓冲层技术进行了材料生长,首先在SI衬底上外延gE缓冲层,随后生长32 nM SI0.16gE0.84和12 nM gE,并生长1 nM SI作为钝化层。使用原子力显微镜和X射线衍射对材料形貌和晶体质量进行表征,在源漏区沉积nI薄膜并退火形成nIgE/gE肖特基结,制备的P型沟道肖特基源漏MOSfET,其未掺杂gE/SIgE异质结构MOSfET器件的空穴有效迁移率比相同工艺条件制备的硅器件的高1.5倍,比传统硅器件空穴有效迁移率提高了80%,掺杂器件的空穴有效迁移率与传统硅器件的相当。Si-based Ge /SiGe heterostructure Schottky barrier source and drain metal oxide semiconductor field effect transistors( SB-MOSFETs) with hafnium dioxide high-k gate were fabricated.The effect of the n-type doped Si 0.16 Ge 0.84 layer on the device performance was investigated,and the mechanism of the device off-state current reduction caused by the n type doping SiGe layer was analyzed.Firstly,Ge buffer was fabricated with low-temperature Ge buffer technique.Then a 32 nm Si 0.16 Ge 0.84 layer and a 12 nm Ge layer were grown on the Ge buffer in the same UHVCVD system.For comparative study, the 32 nm Si 0.16 Ge 0.84 layer was controlled undoped or n-type doped by P.For all samples,1 nm Si layer was grown to passivate the Ge surface.Atomic force microscopy and X-ray diffraction were used to characterize the surface morphology and crystal quality of the materials.NiGe / Ge Schottky junctions in source and drain were formed by nickel layer deposition and anneal.The fabricated Ge / SiGe heterosturctual MOSFET device without n-type doping shows 150% enhancement of the hole effective mobility over that of the control Si device and about 80% enhancement over the universal Si device.And the device with n-type doping shows a comparable hole effective mobility with the universal Si MOSFET device.国家自然科学基金资助项目(61036003;61176092); 国家重点基础研究发展计划(973计划)资助项目(2012CB933503;2013CB632103); 中央高校基本科研业务费资助项目(2010121056