Print Email Facebook Twitter X-ray investigation of buried SiGe islands for devices with strain-enhanced mobility Title X-ray investigation of buried SiGe islands for devices with strain-enhanced mobility Author Hrauda, N. Zhang, J.J. Stangl, J. Rehman-Khan, A. Bauer, G. Stoffel, M. Schmidt, O.G. Jovanovich, V. Nanver, L.K. Faculty Electrical Engineering, Mathematics and Computer Science Department Microelectronics Date 2009-03-30 Abstract In this work self-organized SiGe islands are used as stressors for Si capping layers, which later act as carrier channels in field effect transistors. To be able to address individual islands and to obtain a sufficiently narrow distribution of their properties, the SiGe islands are grown by molecular beam epitaxy on prepatterned Si substrates, with a regular two-dimensional array of pits. This combination of lithographic patterning and self-assembled island growth combines the advantages of both approaches and leads to very homogeneous island shape, size, and chemical composition. For processing, 4?in. wafers are used, and fields with pit periods between 600 and 1000?nm are defined by optical lithography. After growth of a Si buffer layer several monolayers of Ge are deposited, leading to island formation (dome or barn shaped) in the pits. Subsequent Si capping is performed at a low substrate temperature of 300?°C to avoid intermixing and shape changes of the buried islands. The Ge distribution in the buried islands and the strain distribution in the islands and the surrounding Si matrix are assessed by x-ray diffraction experiments, combined with three-dimensional model simulations using finite elements. Tensile strain values in the Si cap up to 8×10?3 can be achieved using this approach, which is difficult to achieve using other methods without introduction of dislocations. Subject buffer layerscarrier mobilitychemical analysisfield effect transistorsfinite element analysisGe-Si alloysisland structuremolecular beam epitaxial growthmonolayersphotolithographyself-assemblysemiconductor epitaxial layerssemiconductor growthsemiconductor materialstensile strengthX-ray diffraction To reference this document use: http://resolver.tudelft.nl/uuid:89a023ae-52eb-4136-8a34-8745ecc28364 Publisher American Vacuum Society ISSN 1071-1023 Source https://doi.org/10.1116/1.3056178 Source Journal of Vacuum Science & Technology B, 27 (2), 2009 Part of collection Institutional Repository Document type journal article Rights © 2009 American Vacuum Society Files PDF Jovanovich_2009.pdf 647.59 KB Close viewer /islandora/object/uuid:89a023ae-52eb-4136-8a34-8745ecc28364/datastream/OBJ/view