Atomic processes during Cl supersaturation etching of Si(100)-(2Ã1)
نویسندگان
چکیده
Supersaturation etching starts with Cl insertion into Si-Si bonds of Si 100 and leads to the desorption of SiCl2 pairs. During etching, insertion occurs through a Cl2 dissociative chemisorption process mediated by single dangling bond sites created by phonon-activated electron-stimulated desorption of atomic Cl. Based on scanning tunneling microscopy results, we identify a surface species, describe its involvement in supersaturation etching, and explore the energetics that control this process. In doing so, we show that insertion occurs at room temperature and that paired dangling bonds of bare dimers also mediate this process.
منابع مشابه
Cl insertion on Si(100)-(2x1): etching under conditions of supersaturation.
We use scanning tunneling microscopy to show that Cl2 dosing of Cl-saturated Si(100)-(2x1) surfaces at elevated temperature leads to uptake beyond "saturation" and allows access to a new etching pathway. This process involves Cl insertion in Si-Si dimer bonds or backbonds, diffusion of the inserted Cl, and ultimately desorption of SiCl2. Investigations into the etch kinetics reveal that inserti...
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