AVS 50th International Symposium
    Surface Science Tuesday Sessions
       Session SS-TuP

Paper SS-TuP12
Crater Wall Shape Evolution During Annealing Induced Flattening of Si(001)

Tuesday, November 4, 2003, 5:30 pm, Room Hall A-C

Session: Poster Session
Presenter: B.J. Gibbons, The Ohio State University
Authors: B.J. Gibbons, The Ohio State University
J.P. Pelz, The Ohio State University
Correspondent: Click to Email
We have studied high temperature annealing induced flattening of large (up to 50 µm@super 2@) "craters", formed using a new double wet thermal oxidation process on silicon (001). This process was used to eliminate the initial "trenching" around the perimeter of the crater floor that can occur during normal dry etching procedures. It has been suggested that such trenching can interfere/delay the process of flattening.@footnote 1@ Surprisingly, we have found that trenches are formed during extended annealing even if not initially present, as well as a "peak" around the upper crater wall perimeter. Above the roughening temperature (~ 1200 °C for Si(001)) the profile of the crater wall can be described using a continuum model.@footnote 2@ For temperatures below roughening the trench and peak features can be qualitatively described using microscopic step models,@footnote 3@ although a good quantitative description has not yet been achieved. To date we are able to remove the initial sample miscut over an area of up to 30 x 40 µm@super 2@, leaving behind a region with concentric closed steps formed by pit nucleation.@footnote 4@ We will discuss the optimum conditions for creating large flat regions "blindly", as well as ongoing electromigration experiments in the presence of a Si flux. @FootnoteText@@footnote 1@Tanaka, et al., Appl. Phys. Lett., 69(9), 26 Aug. 1996 @footnote 2@W.W. Mullins, J. Appl. Phys. 28(3), Mar 1957 @footnote 3@Liu, et al., J. Vac. Sci. Technol. B 14(4), Jul/Aug 1996) @footnote 4@J.-F. Nielsen, et al., Phys. Rev. Lett. 87(13), 24 Sep. 2001