S10747-0909 Datasheet, PDF (2/7 Pages) Hamamatsu Corporation – Enhanced near-infrared sensitivity by using fully-depleted CCD technology

CCD area image sensor
S10747-0909
Structure of fully-depleted back-illuminated CCD
Back-thinned CCDs the silicon substrate is only a few dozen microns thick. This means that near-infrared light is more likely to pass
through the substrate (see Figure 1), thus resulting in a loss of quantum efficiency in infrared region. Thickening the silicon substrate
increases the quantum efficiency in the near-infrared region but also makes the resolution worse since the generated charges diffuse
into the neutral region unless a bias voltage is applied (see Figure 2). Fully-depleted back-illuminated CCDs use a thick silicon sub-
strate that has no neutral region when a bias voltage is applied and therefore deliver high quantum efficiency in the near-infrared re-
gion while maintaining a good resolution (see Figure 3). One drawback, however, is that the dark current becomes large so that these
devices must usually be cooled to about -70 °C during use.
[Figure 1] Back-thinned CCD
[Figure 2] When no bias voltage is
applied to thick silicon
CCD surface
[Figure 3] When a bias voltage is applied to
thick silicon (fully-depleted back-
illuminated CCD)
CCD
surface
CCD side
Depletion
layer
GND
Photosensitive
surface
Blue light Near-infrared light
Charge
diffusion
Depletion
layer
Neutral
region
GND
Photosensitive
surface
Blue light Near-infrared light
Depletion
layer
BIAS
Photosensitive
surface
Blue light Near-infrared light
KMPDC0332EA
Absolute maximum ratings (Ta=-70 °C)
Parameter
Symbol
Min.
Typ.
Max.
Unit
Operating temperature
Topr
-120
-
+30
°C
Storage temperature
Tstg
-200
-
+70
°C
Substrate voltage (applied bias voltage)
Vss
-0.5
-
+30
V
OD voltage
VOD
-25
-
+0.5
V
RD voltage
VRD
-18
-
+0.5
V
ISV voltage
VISV
-18
-
+0.5
V
ISH voltage
VISH
-18
-
+0.5
V
IGV voltage
VIG1V, VIG2V
-15
-
+10
V
IGH voltage
VIG1H, VIG2H
-15
-
+10
V
SG voltage
VSG
-15
-
+10
V
OG voltage
VOG
-15
-
+10
V
RG voltage
VRG
-15
-
+10
V
TG voltage
VTG
-15
-
+10
V
Vertical clock voltage
VP1V, VP2V
-15
-
+10
V
Horizontal clock voltage
VP1H, VP2H
-15
-
+10
V
2