In situ study of surface phenomena by real time phase shift interferometry

• Published in: Journal of crystal growth Vol. 137; no. 3; pp. 610 - 622
• Main Authors: Onuma, Kazuo, Kameyama, Tetsuya, Tsukamoto, Katsuo
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.04.1994; Elsevier
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Interferometers; Materials science; Methods of crystal growth; physics of crystal growth; Optical instruments, equipment and techniques; Phase shifting interferometry; Physics; Solid surfaces and solid-solid interfaces; Surface structure and topography; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Theory and models of film growth; Real time systems; Inorganic compounds; Phase shift; Ternary compounds; In situ; Surfaces; Step; Experimental study; Sensitivity; Barium nitrates; Crystal growth from solutions; Kinetics; Interferometry
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/0022-0248(94)91006-5

Real time phase shift interferometry is applied to the observation of a growing crystal surface. Detailed profiles of a growth hillock, such as local vibrations of slopes and height differences of growth steps, are clearly distinguished on a barium nitrate crystal, together with measurements of growth rate at each location. It was found that the height difference of 0.92 nm was directly detectable in this interferometry, indicating that the present method is a few ten times more sensitive than conventional two-beam interferometry, applicable to in situ study, such as Michelson interferometry. It was found that: (1) Step spacing gradually increases as a step approaches the edge of a crystal, which is inferred from the non-uniformity of surface supersaturation. (2) The observation of fluctuation of the growth rate under a constant condition was analyzed as due to the unequal separation of neighboring dislocations which produce the pertubation of steps.