Photon-Timing Jitter Dependence on Injection Position in Single-Photon Avalanche Diodes

Abstract

In recent years, a growing number of applications demand better timing resolution from single-photon avalanche diodes (SPADs). The challenge is pursuing improved timing resolution without impairing other device characteristics such as quantum efficiency and dark count rate. This task requires a clear understanding of the statistical phenomena involved in the avalanche current growth in order to drive the device engineering process. Past studies state that in Si SPADs the avalanche injection position statistics is the main contribution to the photon-timing jitter. However, in recent re-engineered devices, this assumption has been questioned. To address this issue, we developed an experimental setup capable of characterizing the photon-timing jitter as a function of the injection position by means of a laser focused on the device active area. The results not only confirmed that the injection position statistics is not the main contribution to photon-timing jitter, but also evidenced interesting dependences of the timing performances on the injection position. Furthermore, we found a relationship between the photon-timing jitter and the specific resistance of the devices, which has been investigated by means of photoluminescence measurements

Recent Advances and Future Perspectives of Single‐Photon Avalanche Diodes for Quantum Photonics Applications

“…As a result, the carriers progressively diffuse, triggering the avalanche also in the area surrounding the filament. The multiplication‐assisted diffusion contributes to statistical fluctuations for two reasons [ 62 ] : on the one hand, the process itself is noisy because it relies on random phenomena (diffusion and impact ionization); on the other hand, the geometry of propagation depends on the position of photon absorption (e.g., in the center or at the edge of the detector), which is random as well. The second contribution to lateral propagation is due to hot carriers in the filament, which can cause the emission and subsequent absorption of secondary photons potentially triggering another avalanche also in another region of the same detector.…”

Silicon technologies for arrays of Single Photon Avalanche Diodes

“…This fact results in a remarkable increase of the SPAD series resistance. This is especially undesirable from the point of view of the temporal resolution; in fact, it has been demonstrated [39] that an increase of the series resistance reduces the avalanche growth rate leading to a worsening of the photon timing jitter. A very effective and general solution to this problem, perfectly compatible with the fabrication of arrays, comes once again from the use of deep trenches.…”

Development of new photon-counting detectors for single-molecule fluorescence microscopy

“…An advantage of the thin SPAD technology developed by Politecnico di Milano is the much narrower IRF, which can reach a few tens of picoseconds for 50-200 mm diameter detectors [72,73]. As mentioned earlier, however, until recently these detectors suffered from lower QE than the thick reach-through SPADs in the red region of the spectrum, due mainly to their thinner absorption region.…”