Single-fabrication-step Ge nanosphere/SiO2/SiGe heterostructures: a key enabler for realizing Ge MOS devices. (19th March 2018)

• Record Type: Journal Article
• Authors: Liao, P H; Peng, K P; Lin, H C; George, T; Li, P W
• Is Part Of: Nanotechnology. Volume 29:Number 20(2018)
• Publication Date: 2018-03-19
• Subjects: MOS -- germanium quantum dot -- SiGe -- self-organization -- channel engineering -- strain engineering; 73.21.La -- 79.60.Jv -- 81.10.−h -- 81.40.Jj -- 81.65.Mq -- 82.65.+r; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/aab17b
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: We report channel and strain engineering of self-organized, gate-stacking heterostructures comprising Ge-nanosphere gate/SiO2 /SiGe-channels. An exquisitely-controlled dynamic balance between the concentrations of oxygen, Si, and Ge interstitials was effectively exploited to simultaneously create these heterostructures in a single oxidation step. Process-controlled tunability of the channel length (5–95 nm diameters for the Ge-nanospheres), gate oxide thickness (2.5–4.8 nm), as well as crystal orientation, chemical composition and strain engineering of the SiGe-channel was achieved. Single-crystalline (100) Si1− x Ge x shells with Ge content as high as x = 0.85 and with a compressive strain of 3%, as well as (110) Si1− x Ge x shells with Ge content of x = 0.35 and corresponding compressive strain of 1.5% were achieved. For each crystal orientation, our high Ge-content, highly-stressed SiGe shells feature a high degree of crystallinity and thus, provide a core 'building block' required for the fabrication of Ge-based MOS devices.