AVS 51st International Symposium
    Dielectrics Thursday Sessions
       Session DI+PS-ThA

Paper DI+PS-ThA8
Ultra Thin Oxides and Nitrides on Si: Growth and Properties

Thursday, November 18, 2004, 4:20 pm, Room 304B

Session: Oxides on Semiconductors
Presenter: P. Morgen, SDU Odense, Denmark
Authors: P. Morgen, SDU Odense, Denmark
U. Robenhagen, SDU Odense, Denmark
A. Bahari, SDU Odense, Denmark
M.G. Rao, IISc, India
K. Pedersen, Aalborg University, Denmark
Correspondent: Click to Email
Various conditions for slow growth of ultra thin silicon oxides on Si have been studied, at relatively low temperatures and pressures, in an ultra high vacuum environment. In this way a hitherto unknown regime in pressure-temperature space has been discovered including a fast (ballistic) stage terminating with a self-limiting oxidation. This precedes and deviates radically from the high temperature-high pressure Deal-Grove mechanism. Several different schemes are invented leading to oxide thicknesses from about 0.4 to 0.7 nm, with high quality of the interface and uniformity of coverage. Our present and previous studies connect the initial steps of oxygen adsorption and reaction at room temperature with the first steps (and barriers) to form three dimensional oxides on two Si surfaces (111) and (100). The structural information is obtained by following these oxidation reactions with photoemission spectroscopy, including high resolution, surface sensitive core-level photoemission; STM; LEED; optical second harmonic generation spectroscopy, and Auger electron spectroscopy. Similar procedures are followed to create ultra thin nitrides using microwave dissociated nitrogen. This process is already known to be self limiting, but at a somewhat higher film thickness than for the growth of oxides. The prospect of doping these oxides with nitrogen, and these nitrides with oxygen, is also successfully explored.