452
A. Maizelis and B. Bairachniy
For 3DI process the fitting parameters [56]
k 3d 1 =
zF D 1/2 c
π 1/2 ,
(28.12)
k 3d 2 = N 0 π(
8πcM
ρ
)
1/2
(28.13)
are presented in Table 28.2.
Values of the diffusion coefficients calculated using the fitting parameters
according to Eq. (28.4) are shown in Fig. 28.4, curve 2. These values of the diffusion
coefficients are close to those obtained using the slopes of the current transients in
Cottrell coordinates (curve 3). Besides that, these values are between the known
ones for ammonia [2, 57, 58] and pyrophosphate [9, 42, 43] electrolytes (taking
into account the difference in the copper ion concentrations and pH of these
electrolytes).
The semilogarithmic dependence of nuclei number on deposition potential is
shown in Fig. 28.9. Increase in the polarization up to deposition potential of −0.8 V
leads to the sharp increase in nuclei number. Since the height of 2D copper nuclei
layer increases at the same time (Fig. 28.8), the continuous copper films form at the
Table 28.2 The fitting
parameters of 3DI copper
nucleation and growth
E, V k 3D 1 , mAcm −2 s 1/2 k 3D 2 , s −1
−0.6 15.9
2.14
−0.7 18.9
3.18
−0.8 20.6
5.66
−0.9 20.3
5.75
−1.0 21.5
6.87
−1.1 24.2
7.60
Fig. 28.8 Copper layer
height dependence on
deposition potential
A. Maizelis and B. Bairachniy
For 3DI process the fitting parameters [56]
k 3d 1 =
zF D 1/2 c
π 1/2 ,
(28.12)
k 3d 2 = N 0 π(
8πcM
ρ
)
1/2
(28.13)
are presented in Table 28.2.
Values of the diffusion coefficients calculated using the fitting parameters
according to Eq. (28.4) are shown in Fig. 28.4, curve 2. These values of the diffusion
coefficients are close to those obtained using the slopes of the current transients in
Cottrell coordinates (curve 3). Besides that, these values are between the known
ones for ammonia [2, 57, 58] and pyrophosphate [9, 42, 43] electrolytes (taking
into account the difference in the copper ion concentrations and pH of these
electrolytes).
The semilogarithmic dependence of nuclei number on deposition potential is
shown in Fig. 28.9. Increase in the polarization up to deposition potential of −0.8 V
leads to the sharp increase in nuclei number. Since the height of 2D copper nuclei
layer increases at the same time (Fig. 28.8), the continuous copper films form at the
Table 28.2 The fitting
parameters of 3DI copper
nucleation and growth
E, V k 3D 1 , mAcm −2 s 1/2 k 3D 2 , s −1
−0.6 15.9
2.14
−0.7 18.9
3.18
−0.8 20.6
5.66
−0.9 20.3
5.75
−1.0 21.5
6.87
−1.1 24.2
7.60
Fig. 28.8 Copper layer
height dependence on
deposition potential