Image Processing Reference
In-Depth Information
V
G
Gate electrode
SiO
2
p
-type silicon
FIGURE 2.9
Cross-sectional view of MOS structure with gate electrode-silicon dioxide film (SiO
2
)
p
-type silicon structure.
(a)
Gate electrode
(c)
p
-type Si
SiO
2
V
G
< 0 V
V
G
= 0 V
p
p
Accumulation layer
(b)
(d)
Bandgap of SiO
2
V
G
< 0 V
Conduction band
Conduction band
V
G
= 0 V
p
p
- 0 V
- 0 V
Valence band
Valence band
Accumulation layer
: Electron
: Hole
: Acceptor
: Ionized acceptor
FIGURE 2.10
Spatial and potential distribution model of MOS structure at various gate biases: (a) spatial distribution (flat-band
condition); (b) potential distribution (flat-band condition); (c) spatial distribution (surface accumulation layer);
(d) potential distribution (surface accumulation layer); (e) spatial distribution (shallow depletion); (f) potential
distribution (shallow depletion); (g) spatial distribution (deep depletion, without electron supplier to surface);
(h) potential distribution (deep depletion); (i) spatial distribution (surface inversion layer, with electron supplier
to surface); (j) potential distribution (surface inversion layer).
