DYNAMIC GROWTH STEPS OF NXN DIMER-ADATOM-STACKING-FAULT DOMAINS ON THE QUENCHED SI(111) SURFACE

Dynamic growth steps of Si(111)-n x n dimer-adatom-stacking-fault (DAS ) domains in the 1 x 1 matrix have been investigated on quenched Si(11 1) surfaces, with high-temperature scanning tunneling microscopy. It h as been found that both growth and annihilation of n x n DAS domains o ccur with a single n x n stacking-fault (SF) half cell as the building unit. Not only 7 x 7, but also 9 x 9 DAS domains have been observed t o gradually expand on the quenched surface above 450 degrees C. Every type of nxn DAS domains grows with a successive addition of single SF half cells to a n x n DAS domain side. Structural transformation of 7 x 7 and 11 x 11 SF half cells into 9 x 9 SF half cells occurs at a 9 x 9 domain side, to form a large 9 x 9 DAS domain on the quenched Si(11 1) surface.