BARBIER, Remi (University of Lyon 1 - IPNL) - NDIP 11 - IN2P3

Part II: Solid State devices : PD basic
the PN junction with reverse bias: PhotoDiode
Si bulk => N layer (Phosphor doped);
P layer on top (Boron doped)
Depleted zone (increased by V inv)
If e/h created in the depleted zone
e- in conduction Band and drift to N layer
h in valence Band drift to P layer
The current is read out with no internal gain.
The PIN Diode:
300 µm of intrinsic (high-purity) layer sandwiched between n+ (P) and p+ (B)
This reduces capacitance (reduce noise) sensitive to red
Quantum efficiency
direct
Rémi Barbier, NDIP 2011, Lyon, France, July 4-8 tutorial : photodetectors
Geiger Mode
v bd
APD
P
-
reverse
PD
V inv
+
i
N
v
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