Effect of B dose and Ge preamorphization energy on the electrical and structural properties of ultrashallow junctions in silicon-on-insulator

Justin J. Hamilton, Erik J H Collart, Benjamin Colombeau, Massimo Bersani, Damiano Giubertoni, Max Kah, Nicholas E B Cowern, Karen J. Kirkby

    Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review


    Formation of highly activated, ultra-shallow and abrupt profiles is a key requirement for the next generations of CMOS devices, particularly for source-drain extensions. For p-type dopant implants (boron), a promising method of increasing junction abruptness is to use Ge preamorphizing implants prior to ultra-low energy B implantation and solid-phase epitaxy regrowth to re-crystallize the amorphous Si. However, for future technology nodes, new issues arise when bulk silicon is supplanted by silicon-on-insulator (SOI). Previous results have shown that the buried Si/SiO2 interface can improve dopant activation, but the effect depends on the detailed preamorphization conditions and further optimization is required. In this paper a range of B doses and Ge energies have been chosen in order to situate the end-of-range (EOR) defect band at various distances from the back interface of the active silicon film (the interface with the buried oxide), in order to explore and optimize further the effect of the interface on dopant behavior. Electrical and structural properties were measured by Hall Effect and SIMS techniques. The results show that the boron deactivates less in SOI material than in bulk silicon, and crucially, that the effect increases as the distance from the EOR defect band to the back interface is decreased. For the closest distances, an increase injunction steepness is also observed, even though the B is located close to the top surface, and thus far from the back interface. The position of the EOR defect band shows the strongest influence for lower B doses.

    Original languageEnglish
    Title of host publicationMaterials Research Society Symposium Proceedings
    Number of pages6
    Publication statusPublished - 2006
    Event2006 MRS Spring Meeting - San Francisco, United States
    Duration: 18 Apr 200619 Apr 2006


    Conference2006 MRS Spring Meeting
    Country/TerritoryUnited States
    CitySan Francisco


    Dive into the research topics of 'Effect of B dose and Ge preamorphization energy on the electrical and structural properties of ultrashallow junctions in silicon-on-insulator'. Together they form a unique fingerprint.

    Cite this