From: hackbard Date: Tue, 24 Aug 2010 18:46:45 +0000 (+0200) Subject: guide for rest of c_i c_s section X-Git-Url: https://hackdaworld.org/gitweb/?a=commitdiff_plain;h=0db2a34362b50a05f5aa3590ffd95b645fd8aecd;p=lectures%2Flatex.git guide for rest of c_i c_s section --- diff --git a/posic/publications/defect_combos.tex b/posic/publications/defect_combos.tex index d6a18da..4ba5207 100644 --- a/posic/publications/defect_combos.tex +++ b/posic/publications/defect_combos.tex @@ -319,9 +319,10 @@ Present results show a difference in energy of states A and B, which exactly mat % mattoni: A favored by 0.4 eV - NO, it is indeed B (reinforce Song and Capaz)! % % AB transition -% ... -The migration barrier was identified to be \unit[0.44]{eV}, almost three times higher than the experimentally obtained value of \unit[0.16]{eV}\cite{song90_2}. -This might be due to +The migration barrier was identified to be \unit[0.44]{eV}, almost three times higher than the experimental value of \unit[0.16]{eV}\cite{song90_2} estimated for the neutral charge state transition in p- and n-type Si. +Keeping in mind the formidable agreement of the energy difference with experiment, the overestimated activation energy is quite unexpected and disappointing. +Obviously, either the CRT algorithm fails to seize the actual saddle point structure or the influence of dopants has exceptional effect in the experimentally covered diffusion process being responsible for the low migration barrier. +% not satisfactory! % a b \begin{figure} @@ -344,14 +345,20 @@ Next to differences in the XC-functional and plane-wave energy cut-off this disc Indeed, investigating the migration path from configurations a to b and, in doing so, reusing the wave functions of the previous migration step the final structure, i.e. configuration b, was obtained with zero magnetization and an increase in configurational energy by \unit[0.2]{eV}. Obviously a different energy minimum of the electronic system is obatined indicating hysteresis behavior. However, since the total energy is lower for the magnetic result it is believed to constitute the real, i.e. global, minimum with respect to electronic minimization. - +% +% a b transition A low activation energy of \unit[0.1]{eV} is observed for the a$\rightarrow$b transition. Thus, configuration a is very unlikely to occur in favor of configuration b. -However, migration barriers yielding -... -% mig a-b +% for 00-1 repulsive interaction in 110 direction, wich is in agreement with results of Mattoni. Tensile strain is the reason. + +% all other investigates results attractive interaction. stress compensation. + +% c agglomeration vs c clustering ... migs to b conf % 2 more migs: 051 -> 128 and 026! forgot why ... probably it's about probability of C clustering +Whether C agglomeration or clustering is expected has, again, been answered by investigating migration barriers. +Therefor, several migration paths were investigated, which result in configuration b. + \subsection{C$_{\text{i}}$ next to V}