= Deferred charge in CCD readout
<Deferred charge in CCD readout> reaches later output samples than its originating packet. <George Elwood Smith> describes <surface states> at the <silicon>–<silicon dioxide> interface capturing <Electrons> and releasing them later, smearing the image. A buried channel keeps the stored packet away from that interface.<Nobel Lecture: The invention and early history of the CCD by George Elwood Smith>[pp. 2310–2311, Figs. 10–11, trapping]{ref}
An original comparison separates two interpretations of the same main-packet deficit. If a single transfer defers fraction $\epsilon$ by exactly one sample and loses nothing, an isolated input packet $N$ produces samples $\eta_{\rm tr}N$ followed by $\epsilon N$: summing both recovers $N$. A truly lossy transfer yields only $\eta_{\rm tr}N$, with no later recovery. For $N=10000$ and $\epsilon=0.01$, both give $9900$ in the intended sample, but only the deferred case gives a $100$-<Electron> trail. Such a trail redistributes position information even when total <electric charge> is conserved. Repeated delays require a time-response model; $N_{\rm in}\eta_{\rm tr}^n$ alone cannot predict trail shape. <Electron-hole recombination>, escape to another contact, or release beyond the recorded window can instead remove signal from the measured sum.
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