The diffusion of individual point defects in a two-dimensional streptavidin crystal formed on biotin-containing supported lipid bilayers was observed by high-speed atomic force microscopy. The two-dimensional diffusion of monovacancy defects exhibited anisotropy correlated with the two crystallographic axes in the orthorhombic C 222 crystal; in the 2D plane, one axis (the a-axis) is comprised o...

Radiation-induced segregation (RIS) of solutes in materials exposed to irradiation is a well-known problem. It affects the lifetime nuclear reactor core components by favoring radiation-induced degradation phenomena such as hardening and embrittlement. In this work, RIS tendencies face centered cubic (fcc) Ni-$X$ ($X=\mathrm{Cr}$, Fe, Ti, Mn, Si, P) dilute binary alloys are examined. The goal i...

Passivity breakdown on HDSS 2707 has been studied and the electrochemical data are interpreted in terms of Point Defect Model. Pitting parameters determined, including polarizability at bl/s interface, defect annihilation rate, diffusion coefficient. The potential is demonstrated to be linearly related log [Br-], pH, square root scan rate (v1/2), follows a near-normal distribution. critical vac...

B diffusion measurements are used to probe the basic nature of self-interstitial point defects in Ge. We find two distinct self-interstitial forms--a simple one with low entropy and a complex one with entropy ∼30  k at the migration saddle point. The latter dominates diffusion at high temperature. We propose that its structure is similar to that of an amorphous pocket--we name it a morph. Compu...

The quality of crystalline silicon highly influences the quality of semiconductor devices fabricated with it. Grown-in defects, such as octahedral voids or networks of large dislocation loops can be detrimental to the functionality of devices. Both type of defects result from the interaction of intrinsic point defects, vacancies and self-interstitials during growth and subsequent annealing of t...

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Laura Oikkonen Name of the doctoral dissertation Atomic-scale defects in solar cell material CuInSe2 from hybrid-functional calculations Publisher School of Science Unit Department of Applied Physics Series Aalto University publication series DOCTORAL DISSERTATIONS 143/2013 Field of research Theoretical and computational physi...

In this work, variations in electron potential are incorporated into a Kinetic Lattice Monte Carlo (KLMC) simulator and applied to dopant diffusion in silicon. To account for the effect of dopants, the charge redistribution induced by an external point charge immersed in an electron (hole) sea is solved numerically using the quantum perturbation method. The local carrier concentrations are then...

Boron exhibits anomalous diffusion during the initial phases of ion implant annealing. Boron transient enhanced diffusion is characterized by enhanced tail diffusion coupled with an electrically inactive immobile peak. The immobile peak is due to clustering of boron in the presence of excess interstitials which also enhance boron diffusion in the tail region. We present a simple model for the f...