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Quenching Scenario. H.Otono, H.Oide 21/Dec/2007. Shockley-Ramo Theorem. Q. -Q. x i. x f. v. v. q. q. E. E. j. j. If j (X i )=0 and j (X f )=j,. S-R Theorem in PIN Photo Diode. photon. Q. -Q. h. v. v. e. E. j. Finally,. Derivation of S-R theorem. (1.a). (1.b). (1.c).
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Quenching Scenario H.Otono, H.Oide 21/Dec/2007
Shockley-Ramo Theorem Q -Q xi xf v v q q E E j j If j(Xi)=0 and j(Xf)=j,
S-R Theorem in PIN Photo Diode photon Q -Q h v v e E j Finally,
Derivation of S-R theorem (1.a) (1.b) (1.c) xi xi r(x) No Charge q q E1i E E0 + V V -Q -Q Q Q xf xf (2.a) (2.b) (2.c) r(x) No Charge q q E1f E0 E + V V
S-R Theorem w/ Resistor photon Q’ -Q’ Q v v -Q E R V ’ consist with S-R theorem @RO ’
Excess Carrier Lifetime P-type N-type e h photon 1018 [cm-3] 1018 [cm-3] Q’ -Q -Q’ Q E=0 E>0 E=0 Induced Charge Q’ is a minor carrier Diffuse time ~ 10-13s Multiplied Charge Q is a major carrier Diffuse time ~ 10-13s Recombination timedepends on G-R center density (<10-4s) Multiplied charge is accumulated in diffusion layer After induced current, complementary charge (Q-Q’) flows. . G-R center
S-R Theorem w/ Resistor photon Q v v -Q R Q’ v Q’ -Q’ v R Q’ Q-Q’ Q’-Q Q-Q’ R
S-R Theorem w/ Resistor We have to take into account E variation due to current fed into attached resistor, but it is about O(⊿V/ V). Therefore we can estimate the ratio of the1st pulse to total pulse. j = 63.5 [v] G = 5.0e5 E = 3.0e7 [V/m] v = 1.0e5 [m/s] ( )
Pulse Shape 200K 77K 300K Tail Tail Spike Spike Overestimating….?
Well-known Quench Mechanism V-IR>V0 V I I e- h+ R R V V V-I0R=V0 V-IR>V0 I0 I0 I I e- h+ R R V V
Expected Pulse Height We need another quenching mechanism.
Our Proposing Quench Mechanism E>E0 E I I h+ e- R R V V E=E0 E>E0 I0 h+ e- I0 I I R R V V
Gain Locality in pixel y-point (1 mm pitch) x-point (1 mm pitch)
Electric Field Calculation Electric field has to be reduced about Multiplied carriers as a condenser generate Our mechanism decides multiplication factor (=G) w/o capacitance value. But the carriers have to be diffuse in every corner in pixel.
Diffusion Mechanism • Lattice scattering Low energy Scattering by doping ion High energy Scattering by phonon • Charge Repulsion (where r 0=10nm, r=20nm)
Velocity Saturation (C.Jacoboni et al."Solid-State Electron,20,77(1977))