Diffusion of Hydrogen in 6H Silicon Carbide

1996 ◽  
Vol 423 ◽  
Author(s):  
M. K. Linnarsson ◽  
J. P. Doyle ◽  
B. G. Svensson

Abstract6H polytype silicon carbide (SiC) samples of n-type have been implanted with 50 keV H+ ions and subsequently annealed at temperatures between 200 °C and 1150 °C. Using depth profiling by secondary ion mass spectrometry motion of hydrogen is observed in the implanted region for temperatures above 700 °C. A diffusion coefficient of ∼10−14 cm2/s is extracted at 800°C with an approximate activation energy of ∼3.5 eV. Hydrogen displays strong interaction with the implantation-induced defects and stable hydrogen-defect complexes are formed. These complexes anneal out at temperatures in excess of 900°C and are tentatively identified as Carbon-Hydrogen centers at a Si vacancy.

1988 ◽  
Vol 126 ◽  
Author(s):  
P. Mel ◽  
S. A. Schwarz ◽  
T. Venkatesan ◽  
C. L. Schwartz ◽  
E. Colas

ABSTRACTTe enhanced mixing of AlAs/GaAs superlattice has been observed by secondary ion mass spectrometry. The superlattice sample was grown by organometallic chemical vapor deposition and doped with Te at concentrations of 2×1017 to 5×1018 cm−.3 In the temperature range from 700 to 1000 C, a single activation energy for the Al diffusion of 2.9 eV was observed. Furthermore, it has been found that the relationship between the Al diffusion coefficient and Te concentration is linear. Comparisons have been made between Si and Te induced superlattice mixing.


1998 ◽  
Vol 513 ◽  
Author(s):  
M. Janson ◽  
M. K. Linnarsson ◽  
A. Hallén ◽  
B. G. Svensson

ABSTRACTEpitaxial layers of low doped 4H-SiC are implanted with 20 keV 2H+ ions to a dose of 1×1015 cm−2. The samples are subsequently annealed at temperatures ranging from 1040 to 1135 °C. Secondary ion mass spectrometry is used to obtain the concentration versus depth profiles of the atomic deuterium in the samples. It is found that the concentration of implanted deuterium decreases rapidly in the samples as a function of anneal time.The experimental data are explained by a model where the deuterium migrates rapidly and becomes trapped and de-trapped at implantation-induced defects which exhibit a slightly shallower depth distribution than the implanted deuterium ions. Computer simulations using this model, in which the damage profile is taken from Monte Carlo simulations and the surface is treated as a perfect sink for the diffusing deuterium atoms, are performed with good results compared to the experimental data. The complexes are tentatively identified as carbon-deuterium at a Si-vacancy and a dissociation energy (ED) of approximately 4.9 eV is extracted for the deuterium-vacancy complexes.


2009 ◽  
Vol 1201 ◽  
Author(s):  
Pekka Tapio Neuvonen ◽  
Lasse Vines ◽  
Klaus Magnus Johansen ◽  
Anders Hallén ◽  
Bengt Gunnar Svensson ◽  
...  

AbstractSecondary ion mass spectrometry has been applied to study the transportation of Na and Li in hydrothermally grown ZnO. A dose of 1015 cm-2 of Na+ was implanted into ZnO to act as a diffusion source. A clear trap limited diffusion is observed at temperatures above 550 °C. From these profiles, an activation energy for the transport of Na of ∼1.7 eV has been extracted. The prefactor for the diffusion constant and the solid solubility of Na cannot be deduced independently from the present data but their product estimated to be ∼3 × 1016 cm-1s-1. A dissociation energy of ∼2.4 eV is extracted for the trapped Na. The measured Na and Li profiles show that Li and Na compete for the same traps and interact in a way that Li is depleted from Na-rich regions. This is attributed to a lower formation energy of Na-on-zinc-site than that for Li-on-zinc-site defects and the zinc vacancy is considered as a major trap for migrating Na and Li atoms. Consequently, the diffusivity of Li is difficult to extract accurately from the present data, but in its interstitial configuration Li is indeed highly mobile having a diffusivity in excess of 10-11 cm2s-1 at 500 °C.


2017 ◽  
Vol 49 (11) ◽  
pp. 1057-1063 ◽  
Author(s):  
Kyung Joong Kim ◽  
Jong Shik Jang ◽  
Joe Bennett ◽  
David Simons ◽  
Mario Barozzi ◽  
...  

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