Study of the (7 × 7) ↔ (1 × 1) Si(111) surface transition by spectroscopic ellipsometry near the pseudo-Brewster angle

Abstract

In this paper we study the (7 × 7) ↔ (1 × 1) Si(111) surface transition by using spectroscopic ellipsometry near the pseudo-Brewster (PB) angle. At PB energy, tg Ψ (respectively cos Δ) increases (decreases) linearly with different slopes according to T < T c or T > T c . These two different slopes correspond to the two different (7 × 7) and (1 × 1) superstructures. Around T c , Ψ deviates from linearity. This effect is attributed to an electrostatic interaction between (7 × 7) and (1 × 1) domains.