ISSN:
1618-2650
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Homogeneous ultra thin silicon nitride layers (SiNx layers) close to the surface have been produced by 10 keV 15N 2 + molecular ion implantation and an ion current density of 10 μA/cm2, into single crystal silicon at room temperature. Stoichiometric SiNx layers with thicknesses of about 28 nm (analyzed by NRA) were obtained at fluences of 1.5×1017 at/cm2. NRA analyses of samples annealed by EB-RTA at T=1150° C for 15 s indicated that the N/Si ratio and the layer thickness did not change drastically. FT IR ellipsometry analyses indicated the existence of Si3N4 bonds in as-implanted specimens. A disordered Si layer (d-Si, typically 15 nm thick) underneath the implantation region caused by the ion implantation was found by channeling RBS analyses. The d-Si layer partly recrystallized during EB-RTA showing a thickness of 6 nm afterwards. The SiNx layers showed no decomposition and detachment after EB-RTA. Due to EB-RTA, however, the smooth surface of the as-implanted specimens changed into a surface with remaining whisker-like structures surrounded by circular recesses as shown by AFM analyses. A model for the growth of these whisker-liker structures caused by low energy ion implantation and EB-RTA is presented on the basis of the thickness of the SiNx layer, the existence of the d-Si layer and the special annealing process.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00321360
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