TY  - JOUR
PY  - 2004//
TI  - The relation between phase transformation and onset of thermal degradation in nanoscale CoSi 2-polycrystalline silicon structures
JO  - Journal of applied physics
A1  - Van Dal, M.J.H.
A1  - Jawarani, D.
A1  - Van Berkum, J.G.M.
A1  - Kaiser, M.
A1  - Kittl, J.A.
A1  - Vrancken, C.
A1  - De Potter, M.
A1  - Lauwers, A.
A1  - Maex, K.
SP  - 7568
EP  - 7573
VL  - 96
IS  - 12
N2  - Insight in the thermal degradation phenomena and the relation to phase transformation is presented for cobalt disilicide (CoSi 2) on narrow polysilicon lines (linewidth ranging from 30 nm to 1 μm) using electrical and morphological analysis in the temperature range 650-900°C. When polysilicon lines are scaled laterally to 30 nm, an abrupt CoSi 2 sheet resistance increase (>1000 Ω/sq) is observed, which is attributed to silicide agglomeration. At localized positions along the 30-nm Co-silicided lines, Si/silicide layer inversion is observed. At low formation temperature (650°C), no agglomeration phenomena occur, but incidentally the transition from CoSi into CoSi 2 is delayed on the 30-nm-wide polysilicon structures to such an extent that the CoSi 2 growth virtually stops. Only using nitrogen implantation through CoSi and a CoSi 2 formation temperature of 900°C, low sheet resistance values are obtained for 35-nm-wide polysilicon lines. Based on the results obtained in the present work, we propose that the abrupt increase in the CoSi 2 sheet resistance for the narrow polysilicon lines is a consequence of a decrease in the availability of nucleation sites leading to the reduction of the CoSi/CoSi 2 transformation rate, which, in turn, results in the agglomeration of Co suicide at elevated temperature. © 2004 American Institute of Physics.<p /> <p>Language: en</p>
LA  - en
SN  - 0021-8979
UR  - http://dx.doi.org/10.1063/1.1815384
ID  - ref1
ER  -